Arch Womens Ment Health DOI 10.1007/s00737-014-0456-1
ORIGINAL ARTICLE
The role of perceived control over anxiety in prospective symptom reports across the menstrual cycle Jennifer N. Mahon & Kelly J. Rohan & Yael I. Nillni & Michael J. Zvolensky
Received: 12 September 2013 / Accepted: 1 September 2014 # Springer-Verlag Wien 2014
Abstract The present investigation tested the role of psychological vulnerabilities to anxiety in reported menstrual symptom severity. Specifically, the current study tested the incremental validity of perceived control over anxiety-related events in predicting menstrual symptom severity, controlling for the effect of anxiety sensitivity, a documented contributor to menstrual distress. It was expected that women with lower perceived control over anxiety-related events would report greater menstrual symptom severity, particularly in the premenstrual phase. A sample of 49 normally menstruating women, aged 18–47 years, each prospectively tracked their menstrual symptoms for one cycle and completed the Anxiety Control Questionnaire (Rapee, Craske, Brown, & Barlow Behav Ther 27:279–293. doi:10.1016/S0005-7894(96) J. N. Mahon (*) : K. J. Rohan : Y. I. Nillni Department of Psychology, University of Vermont, John Dewey Hall, 2 Colchester Avenue, Burlington, VT 05405-0134, USA e-mail: [email protected]
80018-9, 1996) in their follicular and premenstrual phases. A mixed model analysis revealed perceived control over anxiety-related events was a more prominent predictor of menstrual symptom severity than anxiety sensitivity, regardless of the current cycle phase. This finding provides preliminary evidence that perceived control over anxiety-related events is associated with the perceived intensity of menstrual symptoms. This finding highlights the role of psychological vulnerabilities in menstrual distress. Future research should examine whether psychological interventions that target cognitive vulnerabilities to anxiety may help reduce severe menstrual distress. Keywords Perceived control . Anxiety sensitivity . Premenstrual symptoms . Menstrual cycle
Introduction
K. J. Rohan e-mail: [email protected]
Significance
Y. I. Nillni e-mail: [email protected]
Premenstrual distress is very common, with 90 % of women reporting physiological and psychological symptoms associated with the premenstrual, or late luteal, menstrual phase (Strine et al. 2005; Yonkers et al. 2003). Commonly reported premenstrual symptoms include tension, dysphoria, irritability, pain, impaired concentration, headaches, fatigue, and insomnia (Chrisler and Caplan 2002; Halbreich et al. 2003; Logue and Moos 1986; Yonkers et al. 2003). The premenstrual phase is associated with exacerbations of mood and anxiety disorders such as major depression (Kornstein et al. 2008), premenstrual dysphoric disorder (PMDD; Yonkers et al. 2003), and panic disorder (Breier et al. 1986; Cook et al. 1990; Kaspi et al. 1994). The premenstrual phase also poses notable problems for subclinical and even nonclinical populations, for whom the premenstrual phase is associated
Y. I. Nillni National Center for PTSD, Women’s Health Sciences Division, VA Boston Healthcare System, 150 South Huntington Avenue (116B-3), Boston, MA 02130-4817, USA Y. I. Nillni Boston University School of Medicine, Boston, MA, USA M. J. Zvolensky University of Houston, Heyne Building Room 129, 4800 Calhoun Road, Houston, TX 77004-5022, USA e-mail: [email protected] M. J. Zvolensky MD Anderson Cancer Center, Department of Behavioral Science, The University of Texas, Austin, TX, USA
J.N. Mahon et al.
with functional impairments in sleep and pain as well as increases in depression and anxiety (Gonda et al. 2008; Strine et al. 2005; Yonkers et al. 2003). Theory and background The inter-individual variation in premenstrual symptom severity may relate to individual biological and psychological vulnerabilities. The menstrual reactivity hypothesis (Sigmon et al. 2000c) is a diathesis-stress model that proposes cognitive vulnerabilities to anxiety and depression (i.e., the psychological diathesis) interact with hormonal fluctuations during the menstrual cycle, particularly in the premenstrual phase (i.e., the biological stress) to influence the severity of menstrual symptoms. Heilbrun and Rener (1988) found that nonclinical, normally menstruating women tended to identify the onset of menstruation as an unavoidable stressor, which suggests that even for nonclinical women with regular cycle lengths, the premenstrual phase can be identified as reliably stressful. In terms of candidate cognitive risk factors that may constitute the diathesis, locus of control has been implicated in premenstrual distress. An initial study examining the association between menstrual symptom severity and locus of control (per the Levenson LOC scale; Levenson 1981) in normally menstruating women found that women assessed in the premenstrual phase reported a lower internal locus of control relative to women assessed in the follicular phase, and externality of reported locus of control in the premenstrual phase was associated with greater reported premenstrual symptom severity. However, this study was limited by retrospective reports of premenstrual distress and a cross-sectional sample. Two longitudinal examinations of locus of control across menstrual phases using Rotter’s I-E scale found that women who reported a greater severity of premenstrual symptoms also reported an increased external locus of control in the premenstrual phase relative to themselves at other menstrual phases, and relative to women who reported the overall lower premenstrual symptom severity (Christensen et al. 1992; O’Boyle et al. 1988). In contrast, a third longitudinal study testing the relation of locus of control, as measured by Rotter’s I-E Scale and a clinically derived scale, and premenstrual symptom severity in a sample of normally menstruating women did not show a fluctuation in locus of control across menstrual phases (Martin 1999). There are a variety of possible reasons for the inconclusive literature on locus of control-menstrual symptom relations. First, the lack of convergent findings regarding the association between locus of control and menstrual symptoms may be due to the measurement of global locus of control, nonspecific to stress or anxiety. These prior studies have used measures reflecting a global perception of causality in one’s life, based on the definition by Rotter (1966). Conversely, Barlow (2002) conceptualizes anxiety as involving a sense of uncontrollability over potentially threatening events and negative emotions,
with control defined as the ability to influence events and outcomes in one’s environment (Chorpita & Barlow 1998). Lower perceived control over threatening stimuli is associated with anxious arousal, apprehension, and uncertainty about coping. Consistent with the influential perspective forwarded by Barlow (2002), numerous experimental laboratory-based studies have indicated that persons who lack, or have lost, the perceived ability to terminate exposure to aversive bodily sensations report greater anxiety and panic symptoms than their counterparts who do not lack such perceived control (Sanderson et al. 1989; Telch 1996; Zvolensky et al. 1999; Zvolensky et al. 1998). Researchers have conceptualized lower perceived control over a threat as a shared diathesis for anxiety and depression (Alloy et al. 1990; Barlow 2002). As common menstrual symptoms overlap with anxiety and mood symptoms (e.g., irritability, dysphoria, impaired concentration, fatigue, insomnia, tension, headaches, and pain; Strine et al. 2005), perceived control, as conceptualized by Barlow and colleagues and found to be more central to anxiety and depression, may therefore be more pertinent to the experience of menstrual symptoms. Rapee et al. (1996) developed the Anxiety Control Questionnaire (ACQ) as a specific measure of perceived control to anxiety-related events. Specifically, the ACQ was designed to measure trait-like individual differences in perceived control over internal and external events/situations that are relevant to anxiety and its disorders (Brown et al. 2004; Zebb and Moore 1996; Rapee et al. 1996). Perceived control over anxiety-related events, as measured by the ACQ, is concurrently related to agoraphobic avoidance among persons with panic disorder (White et al. 2006) and panic-relevant interpretative biases for threat among nonclinical individuals (Zvolensky et al. 2001). Although the ACQ has not always been predictive of panic responsivity (e.g., Gregor and Zvolensky 2008), it is possible trait-like perceptions of control over anxiety-related events is relevant to menstrual symptom expression. Second, the current literature examining perceived control as a contributing factor to menstrual distress has largely utilized cross-sectional designs rather than longitudinal designs that allow for a more robust repeated measure test controlling for baseline values and other within-subject variability. Thus, the covariation of cycle fluctuation in perceived control and menstrual symptom reporting within individuals was not considered in the previous work. Third, no study examining the effect of perceived control over anxiety-related events across the menstrual cycle has controlled for the effect of anxiety sensitivity (AS), which has been shown to predict menstrual symptoms (Nillni et al. 2013; Sigmon et al. 1996, 2000a, b), and to serve as a cognitive vulnerability in the diathesis-stress model (Nillni et al. in press; Sigmon et al. 2000c). AS is the fear of anxiety, anxiety-related bodily sensations, and their consequences (Reiss and McNally 1985); individuals high in AS tend to
Perceived control to anxiety and menstrual distress
be hypervigilant to physiological arousal and to misinterpret arousal sensations as dangerous. Given the similarity between anxiety sensations and menstrual symptoms, Sigmon et al. (1996; 2000a, b) tested whether AS also predicted menstrual distress and found that women high in AS reported greater menstrual symptoms across the cycle as compared to low-AS women. Thus, AS appears to be part of the diathesis for enhanced menstrual symptom severity and could represent a potential confound in the previously reported effects of perceived control on menstrual distress. Lastly, results regarding perceived control and menstrual distress may be mixed and inconclusive due to limitations of menstrual phase estimation. Lane and Francis (2003) employed participants’ retrospective recall of the timing of their prior menstrual phase. Martin (1999) assessed the menstrual phase by restricted day count: follicular (day 9), luteal (day 20), and premenstrual (day 26). However, Shirtcliff et al. (2001) reported typical discrepancies between menstrual cycle estimation methods and concluded that menstrual day count alone matched the correct menstrual phase only about 50 % of the time when later verified by progesterone assay. Thus, these different methodological approaches to defining cycle phase status have greatly limited prior studies. Together, the current study aimed to address these limitations by using a prospective, longitudinal design to examine whether perceived control specific to anxiety-related events is implicated in premenstrual distress in normally menstruating women. Specifically, the study tested whether (1) perceived control over anxiety-related events fluctuated between the follicular and premenstrual phases within normally mentruating women and (2) perceived control over anxiety-related events interacts with menstrual phase to specifically predict premenstrual symptom severity, after controlling for AS. It was expected that women would generally report lower perceived control over anxiety in the premenstrual phase relative to the follicular phase and that lower perceived control over anxiety would predict variation in menstrual symptom severity across menstrual phases, even when controlling for AS.
Materials and methods Participants The current study was part of a larger study examining panic responses across the menstrual cycle (Nillni et al. 2012) conducted in the Department of Psychology at the University of Vermont. A total of 65 healthy, normally menstruating women (i.e., average cycle length of 25–35 days that did not regularly vary in length month to month by ≥7 days) initially enrolled in the parent study. The 49 women who completed the prospective daily menstrual symptom tracking over at least one menstrual cycle were included in these
longitudinal analyses. In this sample of 49, participants ranged in age from 18 to 47 years (M=26.20, SD=9.13). The sample characteristics were as follows: 4 % identified as Hispanic, 86 % Caucasian, 4 % as American Indian, 4 % as Asian, 4 % as African American, and 2 % as other; 69 % reported a single marital status. Prior to participation, participants were informed of the study procedures and risks. This research was approved by the Institutional Review Board at the University of Vermont. Measures Anxiety Control Questionnaire 15-item version The ACQ (Rapee et al. 1996) was developed to measure an individual’s perceived control over anxiety and anxiety-related events. Participants rate their level of agreement on a 6-point Likert scale (0=“strongly disagree” to 5=“strongly agree”) for 15 perceived control statements (e.g., “Most events that make me anxious are outside my control”). A confirmatory factor analysis revealed a higher-order factor of perceived control comprised of a 3-factor lower-order solution (emotion control, threat control, and stress control; loadings=.70, .72, .86, respectively; p1 pg/ml. Phase verification was based on progesterone means reported in normally menstruating women (follicular: 80.35 pg/ml, SD=34.8; premenstrual: 136.30 pg/ml, SD=82.3). However, normal variation in progesterone concentration was expected due to assessment timing as progesterone and inter-individual variation in the rate of progesterone decline across the premenstrual phase (Rubinow et al. 1988). Therefore, day count, ovulation, and progesterone were utilized in conjunction to inform phase verification such that menstrual cycle start date and LH peak and were used as primary measures of cycle estimation whereas progesterone level was used as a secondary measure of verification. The follicular phase was considered verified if a positive peak in LH was detected following the follicular laboratory visit or progesterone level was within ±1 SD of mean. The premenstrual phase visit was considered verified if menstruation began within 5 days following the premenstrual lab visit; there was an LH peak detected prior to the visit, or progesterone level was within ±1 SD of mean.
screening visit only. The ASI demonstrated good internal consistency in the current sample (α=.78).
Laboratory visit procedures The study included two laboratory visits, one during the premenstrual phase and one during the follicular phase of the menstrual cycle. To eliminate procedural bias of the study order, the initial cycle phase of testing (i.e., premenstrual or follicular first) was randomly assigned using a pre-generated list of random permuted blocks of sizes 6 and 8. At each visit, participants completed the Anxiety Control Questionnaire (ACQ; Rapee et al. 1996) and provided a saliva sample via passive drool (Salimetrics 2010).
Results Scheduling of laboratory visits and ovulation testing Participants notified the research staff of the day 1 of their menses following the screening visit. The premenstrual phase was defined as the 5 days prior to menstruation onset, and the follicular phase was defined as days 6–12 of the cycle. These day ranges are based on a 28-day cycle and were adjusted for
Premenstrual vs. follicular phase differences in perceived control over anxiety A paired-sample t test (two-tailed) was used to examine whether perceived control to anxiety-related events on the ACQ fluctuates between the premenstrual vs. follicular phases
Perceived control to anxiety and menstrual distress
of the menstrual cycle. As the ACQ was administered at two time points, estimated to be in different menstrual cycle phases, within-subject analyses to test for phase differences in the ACQ included a smaller subset of women (n=38, 78 % of the total sample) for whom both the follicular and premenstrual menstrual phases were confirmed based on the above criteria. Ratings of perceived control over anxiety-related events did not significantly differ between phases [t (37)= −1.49, p=.144], and the ratings appeared quite stable across phases (follicular: M=48.26, SD=10.01; premenstrual: M= 49.45, SD=11.11). Of the 38 women, 14 (29 %) met DRSP criteria for a clinically significant premenstrual symptom severity (PMS), as measured by a greater mean severity of symptoms in the premenstrual phase relative to the follicular phase and by clinical severity rating of at least 5 for at least one symptom in the premenstrual phase (Borenstein et al. 2007). A series of paired sample t tests also examined variation in the ACQ (total and subscale scores) across phases in the women who met for PMS and for whom both phases were also confirmed (N=11). None of the ACQ scores demonstrated differences across phase; ACQ total score, t (10)=−.69, p=.501; EC, t (10)=−.96, p=.359; TC, t (10)=.70, p=.500; and SC, t (10)=−.78, p=.455. The current findings are consistent with the research suggesting that the ACQ demonstrates stability across time and supports the construct validity of the ACQ as a measure of trait perceived control over anxiety-related events (Rapee et al. 1996). Perceived control over anxiety and anxiety sensitivity as predictors of menstrual symptoms In order to examine symptom change across menstrual cycles, only women who completed the DRSP for at least one menstrual cycle were included in this analysis (n=49). To delineate distinct menstrual symptom severity outcomes for each phase of interest, all available days of DRSP data were averaged for each participant, separately during the follicular and premenstrual phases. The mean follicular and premenstrual DRSP outcome variables were then transformed using logarithmic transformation as the raw values were significantly skewed (follicular: skewness=1.36, standard error (SE)= 0.34; premenstrual: skewness=1.77, SE=0.34). The transformation skewness coefficients were improved (follicular: skewness=0.63, SE=0.34; premenstrual: skewness=0.45, SE=0.34). A paired t test on log-transformed DRSP outcomes revealed a greater menstrual symptom severity in the premenstrual phase (M=1.40, SD=0.15) relative to the follicular phase (M=1.31, SD=0.12), t (48)=−5.58, p=.001, d=0.64. Zero-order correlations were computed among variables. The follicular ACQ rating was highly correlated with the premenstrual ACQ rating (r=0.90, p
ORIGINAL ARTICLE
The role of perceived control over anxiety in prospective symptom reports across the menstrual cycle Jennifer N. Mahon & Kelly J. Rohan & Yael I. Nillni & Michael J. Zvolensky
Received: 12 September 2013 / Accepted: 1 September 2014 # Springer-Verlag Wien 2014
Abstract The present investigation tested the role of psychological vulnerabilities to anxiety in reported menstrual symptom severity. Specifically, the current study tested the incremental validity of perceived control over anxiety-related events in predicting menstrual symptom severity, controlling for the effect of anxiety sensitivity, a documented contributor to menstrual distress. It was expected that women with lower perceived control over anxiety-related events would report greater menstrual symptom severity, particularly in the premenstrual phase. A sample of 49 normally menstruating women, aged 18–47 years, each prospectively tracked their menstrual symptoms for one cycle and completed the Anxiety Control Questionnaire (Rapee, Craske, Brown, & Barlow Behav Ther 27:279–293. doi:10.1016/S0005-7894(96) J. N. Mahon (*) : K. J. Rohan : Y. I. Nillni Department of Psychology, University of Vermont, John Dewey Hall, 2 Colchester Avenue, Burlington, VT 05405-0134, USA e-mail: [email protected]
80018-9, 1996) in their follicular and premenstrual phases. A mixed model analysis revealed perceived control over anxiety-related events was a more prominent predictor of menstrual symptom severity than anxiety sensitivity, regardless of the current cycle phase. This finding provides preliminary evidence that perceived control over anxiety-related events is associated with the perceived intensity of menstrual symptoms. This finding highlights the role of psychological vulnerabilities in menstrual distress. Future research should examine whether psychological interventions that target cognitive vulnerabilities to anxiety may help reduce severe menstrual distress. Keywords Perceived control . Anxiety sensitivity . Premenstrual symptoms . Menstrual cycle
Introduction
K. J. Rohan e-mail: [email protected]
Significance
Y. I. Nillni e-mail: [email protected]
Premenstrual distress is very common, with 90 % of women reporting physiological and psychological symptoms associated with the premenstrual, or late luteal, menstrual phase (Strine et al. 2005; Yonkers et al. 2003). Commonly reported premenstrual symptoms include tension, dysphoria, irritability, pain, impaired concentration, headaches, fatigue, and insomnia (Chrisler and Caplan 2002; Halbreich et al. 2003; Logue and Moos 1986; Yonkers et al. 2003). The premenstrual phase is associated with exacerbations of mood and anxiety disorders such as major depression (Kornstein et al. 2008), premenstrual dysphoric disorder (PMDD; Yonkers et al. 2003), and panic disorder (Breier et al. 1986; Cook et al. 1990; Kaspi et al. 1994). The premenstrual phase also poses notable problems for subclinical and even nonclinical populations, for whom the premenstrual phase is associated
Y. I. Nillni National Center for PTSD, Women’s Health Sciences Division, VA Boston Healthcare System, 150 South Huntington Avenue (116B-3), Boston, MA 02130-4817, USA Y. I. Nillni Boston University School of Medicine, Boston, MA, USA M. J. Zvolensky University of Houston, Heyne Building Room 129, 4800 Calhoun Road, Houston, TX 77004-5022, USA e-mail: [email protected] M. J. Zvolensky MD Anderson Cancer Center, Department of Behavioral Science, The University of Texas, Austin, TX, USA
J.N. Mahon et al.
with functional impairments in sleep and pain as well as increases in depression and anxiety (Gonda et al. 2008; Strine et al. 2005; Yonkers et al. 2003). Theory and background The inter-individual variation in premenstrual symptom severity may relate to individual biological and psychological vulnerabilities. The menstrual reactivity hypothesis (Sigmon et al. 2000c) is a diathesis-stress model that proposes cognitive vulnerabilities to anxiety and depression (i.e., the psychological diathesis) interact with hormonal fluctuations during the menstrual cycle, particularly in the premenstrual phase (i.e., the biological stress) to influence the severity of menstrual symptoms. Heilbrun and Rener (1988) found that nonclinical, normally menstruating women tended to identify the onset of menstruation as an unavoidable stressor, which suggests that even for nonclinical women with regular cycle lengths, the premenstrual phase can be identified as reliably stressful. In terms of candidate cognitive risk factors that may constitute the diathesis, locus of control has been implicated in premenstrual distress. An initial study examining the association between menstrual symptom severity and locus of control (per the Levenson LOC scale; Levenson 1981) in normally menstruating women found that women assessed in the premenstrual phase reported a lower internal locus of control relative to women assessed in the follicular phase, and externality of reported locus of control in the premenstrual phase was associated with greater reported premenstrual symptom severity. However, this study was limited by retrospective reports of premenstrual distress and a cross-sectional sample. Two longitudinal examinations of locus of control across menstrual phases using Rotter’s I-E scale found that women who reported a greater severity of premenstrual symptoms also reported an increased external locus of control in the premenstrual phase relative to themselves at other menstrual phases, and relative to women who reported the overall lower premenstrual symptom severity (Christensen et al. 1992; O’Boyle et al. 1988). In contrast, a third longitudinal study testing the relation of locus of control, as measured by Rotter’s I-E Scale and a clinically derived scale, and premenstrual symptom severity in a sample of normally menstruating women did not show a fluctuation in locus of control across menstrual phases (Martin 1999). There are a variety of possible reasons for the inconclusive literature on locus of control-menstrual symptom relations. First, the lack of convergent findings regarding the association between locus of control and menstrual symptoms may be due to the measurement of global locus of control, nonspecific to stress or anxiety. These prior studies have used measures reflecting a global perception of causality in one’s life, based on the definition by Rotter (1966). Conversely, Barlow (2002) conceptualizes anxiety as involving a sense of uncontrollability over potentially threatening events and negative emotions,
with control defined as the ability to influence events and outcomes in one’s environment (Chorpita & Barlow 1998). Lower perceived control over threatening stimuli is associated with anxious arousal, apprehension, and uncertainty about coping. Consistent with the influential perspective forwarded by Barlow (2002), numerous experimental laboratory-based studies have indicated that persons who lack, or have lost, the perceived ability to terminate exposure to aversive bodily sensations report greater anxiety and panic symptoms than their counterparts who do not lack such perceived control (Sanderson et al. 1989; Telch 1996; Zvolensky et al. 1999; Zvolensky et al. 1998). Researchers have conceptualized lower perceived control over a threat as a shared diathesis for anxiety and depression (Alloy et al. 1990; Barlow 2002). As common menstrual symptoms overlap with anxiety and mood symptoms (e.g., irritability, dysphoria, impaired concentration, fatigue, insomnia, tension, headaches, and pain; Strine et al. 2005), perceived control, as conceptualized by Barlow and colleagues and found to be more central to anxiety and depression, may therefore be more pertinent to the experience of menstrual symptoms. Rapee et al. (1996) developed the Anxiety Control Questionnaire (ACQ) as a specific measure of perceived control to anxiety-related events. Specifically, the ACQ was designed to measure trait-like individual differences in perceived control over internal and external events/situations that are relevant to anxiety and its disorders (Brown et al. 2004; Zebb and Moore 1996; Rapee et al. 1996). Perceived control over anxiety-related events, as measured by the ACQ, is concurrently related to agoraphobic avoidance among persons with panic disorder (White et al. 2006) and panic-relevant interpretative biases for threat among nonclinical individuals (Zvolensky et al. 2001). Although the ACQ has not always been predictive of panic responsivity (e.g., Gregor and Zvolensky 2008), it is possible trait-like perceptions of control over anxiety-related events is relevant to menstrual symptom expression. Second, the current literature examining perceived control as a contributing factor to menstrual distress has largely utilized cross-sectional designs rather than longitudinal designs that allow for a more robust repeated measure test controlling for baseline values and other within-subject variability. Thus, the covariation of cycle fluctuation in perceived control and menstrual symptom reporting within individuals was not considered in the previous work. Third, no study examining the effect of perceived control over anxiety-related events across the menstrual cycle has controlled for the effect of anxiety sensitivity (AS), which has been shown to predict menstrual symptoms (Nillni et al. 2013; Sigmon et al. 1996, 2000a, b), and to serve as a cognitive vulnerability in the diathesis-stress model (Nillni et al. in press; Sigmon et al. 2000c). AS is the fear of anxiety, anxiety-related bodily sensations, and their consequences (Reiss and McNally 1985); individuals high in AS tend to
Perceived control to anxiety and menstrual distress
be hypervigilant to physiological arousal and to misinterpret arousal sensations as dangerous. Given the similarity between anxiety sensations and menstrual symptoms, Sigmon et al. (1996; 2000a, b) tested whether AS also predicted menstrual distress and found that women high in AS reported greater menstrual symptoms across the cycle as compared to low-AS women. Thus, AS appears to be part of the diathesis for enhanced menstrual symptom severity and could represent a potential confound in the previously reported effects of perceived control on menstrual distress. Lastly, results regarding perceived control and menstrual distress may be mixed and inconclusive due to limitations of menstrual phase estimation. Lane and Francis (2003) employed participants’ retrospective recall of the timing of their prior menstrual phase. Martin (1999) assessed the menstrual phase by restricted day count: follicular (day 9), luteal (day 20), and premenstrual (day 26). However, Shirtcliff et al. (2001) reported typical discrepancies between menstrual cycle estimation methods and concluded that menstrual day count alone matched the correct menstrual phase only about 50 % of the time when later verified by progesterone assay. Thus, these different methodological approaches to defining cycle phase status have greatly limited prior studies. Together, the current study aimed to address these limitations by using a prospective, longitudinal design to examine whether perceived control specific to anxiety-related events is implicated in premenstrual distress in normally menstruating women. Specifically, the study tested whether (1) perceived control over anxiety-related events fluctuated between the follicular and premenstrual phases within normally mentruating women and (2) perceived control over anxiety-related events interacts with menstrual phase to specifically predict premenstrual symptom severity, after controlling for AS. It was expected that women would generally report lower perceived control over anxiety in the premenstrual phase relative to the follicular phase and that lower perceived control over anxiety would predict variation in menstrual symptom severity across menstrual phases, even when controlling for AS.
Materials and methods Participants The current study was part of a larger study examining panic responses across the menstrual cycle (Nillni et al. 2012) conducted in the Department of Psychology at the University of Vermont. A total of 65 healthy, normally menstruating women (i.e., average cycle length of 25–35 days that did not regularly vary in length month to month by ≥7 days) initially enrolled in the parent study. The 49 women who completed the prospective daily menstrual symptom tracking over at least one menstrual cycle were included in these
longitudinal analyses. In this sample of 49, participants ranged in age from 18 to 47 years (M=26.20, SD=9.13). The sample characteristics were as follows: 4 % identified as Hispanic, 86 % Caucasian, 4 % as American Indian, 4 % as Asian, 4 % as African American, and 2 % as other; 69 % reported a single marital status. Prior to participation, participants were informed of the study procedures and risks. This research was approved by the Institutional Review Board at the University of Vermont. Measures Anxiety Control Questionnaire 15-item version The ACQ (Rapee et al. 1996) was developed to measure an individual’s perceived control over anxiety and anxiety-related events. Participants rate their level of agreement on a 6-point Likert scale (0=“strongly disagree” to 5=“strongly agree”) for 15 perceived control statements (e.g., “Most events that make me anxious are outside my control”). A confirmatory factor analysis revealed a higher-order factor of perceived control comprised of a 3-factor lower-order solution (emotion control, threat control, and stress control; loadings=.70, .72, .86, respectively; p1 pg/ml. Phase verification was based on progesterone means reported in normally menstruating women (follicular: 80.35 pg/ml, SD=34.8; premenstrual: 136.30 pg/ml, SD=82.3). However, normal variation in progesterone concentration was expected due to assessment timing as progesterone and inter-individual variation in the rate of progesterone decline across the premenstrual phase (Rubinow et al. 1988). Therefore, day count, ovulation, and progesterone were utilized in conjunction to inform phase verification such that menstrual cycle start date and LH peak and were used as primary measures of cycle estimation whereas progesterone level was used as a secondary measure of verification. The follicular phase was considered verified if a positive peak in LH was detected following the follicular laboratory visit or progesterone level was within ±1 SD of mean. The premenstrual phase visit was considered verified if menstruation began within 5 days following the premenstrual lab visit; there was an LH peak detected prior to the visit, or progesterone level was within ±1 SD of mean.
screening visit only. The ASI demonstrated good internal consistency in the current sample (α=.78).
Laboratory visit procedures The study included two laboratory visits, one during the premenstrual phase and one during the follicular phase of the menstrual cycle. To eliminate procedural bias of the study order, the initial cycle phase of testing (i.e., premenstrual or follicular first) was randomly assigned using a pre-generated list of random permuted blocks of sizes 6 and 8. At each visit, participants completed the Anxiety Control Questionnaire (ACQ; Rapee et al. 1996) and provided a saliva sample via passive drool (Salimetrics 2010).
Results Scheduling of laboratory visits and ovulation testing Participants notified the research staff of the day 1 of their menses following the screening visit. The premenstrual phase was defined as the 5 days prior to menstruation onset, and the follicular phase was defined as days 6–12 of the cycle. These day ranges are based on a 28-day cycle and were adjusted for
Premenstrual vs. follicular phase differences in perceived control over anxiety A paired-sample t test (two-tailed) was used to examine whether perceived control to anxiety-related events on the ACQ fluctuates between the premenstrual vs. follicular phases
Perceived control to anxiety and menstrual distress
of the menstrual cycle. As the ACQ was administered at two time points, estimated to be in different menstrual cycle phases, within-subject analyses to test for phase differences in the ACQ included a smaller subset of women (n=38, 78 % of the total sample) for whom both the follicular and premenstrual menstrual phases were confirmed based on the above criteria. Ratings of perceived control over anxiety-related events did not significantly differ between phases [t (37)= −1.49, p=.144], and the ratings appeared quite stable across phases (follicular: M=48.26, SD=10.01; premenstrual: M= 49.45, SD=11.11). Of the 38 women, 14 (29 %) met DRSP criteria for a clinically significant premenstrual symptom severity (PMS), as measured by a greater mean severity of symptoms in the premenstrual phase relative to the follicular phase and by clinical severity rating of at least 5 for at least one symptom in the premenstrual phase (Borenstein et al. 2007). A series of paired sample t tests also examined variation in the ACQ (total and subscale scores) across phases in the women who met for PMS and for whom both phases were also confirmed (N=11). None of the ACQ scores demonstrated differences across phase; ACQ total score, t (10)=−.69, p=.501; EC, t (10)=−.96, p=.359; TC, t (10)=.70, p=.500; and SC, t (10)=−.78, p=.455. The current findings are consistent with the research suggesting that the ACQ demonstrates stability across time and supports the construct validity of the ACQ as a measure of trait perceived control over anxiety-related events (Rapee et al. 1996). Perceived control over anxiety and anxiety sensitivity as predictors of menstrual symptoms In order to examine symptom change across menstrual cycles, only women who completed the DRSP for at least one menstrual cycle were included in this analysis (n=49). To delineate distinct menstrual symptom severity outcomes for each phase of interest, all available days of DRSP data were averaged for each participant, separately during the follicular and premenstrual phases. The mean follicular and premenstrual DRSP outcome variables were then transformed using logarithmic transformation as the raw values were significantly skewed (follicular: skewness=1.36, standard error (SE)= 0.34; premenstrual: skewness=1.77, SE=0.34). The transformation skewness coefficients were improved (follicular: skewness=0.63, SE=0.34; premenstrual: skewness=0.45, SE=0.34). A paired t test on log-transformed DRSP outcomes revealed a greater menstrual symptom severity in the premenstrual phase (M=1.40, SD=0.15) relative to the follicular phase (M=1.31, SD=0.12), t (48)=−5.58, p=.001, d=0.64. Zero-order correlations were computed among variables. The follicular ACQ rating was highly correlated with the premenstrual ACQ rating (r=0.90, p
