Appetite, 1992, 19, 145-153
The Relationship Between Changes in Body Weight Changes in Psychosocial Functioning ROBERT
C. KLESGES
and MARY
and
L. KLEM
Center for Applied Psychological Research, Memphis State University
LISA M. KLESGES Department of Biostatistics and Epidemiology, University of Tennessee, Memphis
Previous studies have indicated that obesity is related to a variety of psychosocial problems. Unfortunately, the literature on the relationship between weight status and psychosocial functioning has primarily utilized clinical samples and crosssectional designs. The current study prospectively explored the relationship between weight gain and changes in psychosocial functioning. Subjects were 195 women and 204 men recruited as part of a larger longitudinal study of cardiovascular risk factors, who attended assessment sessions once per year for 2 consecutive years. Psychosocial functioning was assessed using the Dyadic Adjustment Scale (DAS), the Family Environment Scale (FES) and the Family Adaptability and Cohesion Scale 3rd Edition (FACES-III). Subjects were categorized based on their weight status at each year so the effect of a change in weight status on changes in psychosocial functioning could he evaluated. Multivariate measures indicated no changes in psychosocial functioning as a result of change in weight status over a l-year period for either men or women. It appears that shifts in body weight, at least in a sample of subjects with generally good levels of psychological functioning, are not associated with changes in the measured levels of psychosocial functioning.
INTRODUCTION
There is considerable agreement among health professionals regarding the negative health consequences of obesity. Although the precise nature of the relationship between obesity and health is unclear, obesity is clearly related to a higher-than-average risk of coronary heart disease (Van Itallie, 1979), as well as increased occurrence of hypertension, diabetes, arthritis and operative risk (Andres, 1980; Bray, 1976; Keys, 1980). In contrast, the relationship between obesity and psychological health is much less clear. Several investigations have suggested that, when compared to nortnalweight individuals, obese persons are more self-dissatisfied, emotionally unstable,
Address correspondence to: Robert C. Klesges, Center for Applied Psychological Research, Department of Psychology, Memphis State University, Memphis, TN 38120, U.S.A. This study was supported by two grants awarded to the first author (HL36553; HL-39332) by the National Heart, Lung, and Blood Institute. Support was also received from a Centers of Excellence grant awarded to the Department of Psychology, Memphis State University, by the state of Tennessee. 01956663/92/050145+09
$OS.OO/O
0 1992 Academic Press Limited
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R. C. KLESGES ET AL.
apprehensive, passive, non-assertive and depressed (e.g., Hudson & Williams, 1981; Noppa & Hallstrom, 1981; Perelberg, 1978; Pluchik, 1976; Pomerantz et al., 1977). Other studies have concluded that obese individuals are likely to score lower than normal-weight individuals on measures of achievement, affiliation, personal adjustment as well as on measures of family functioning and marital satisfaction (e.g., Banis et al., 1988; Beck & Terry, 1985; Bradley, 1985; Waring, 1983; Wunderlich et al., 1973). An equal number of studies, however, have failed to find a relationship between obesity and these aspects of mental health. For example, Keith & Vanderber (1974) found no differences between obese and normal-weight subjects on an inventory of global personality characteristics, while Segers & Mertens (1974) found obese males to have scores lower than normal-weight and thin males on a measure of depression (indicating a lesser degree of depression). Likewise, Klesges (1984) also found no differences between obese and normal-weight subjects on global measures of depression, assertiveness and self-consciousness. The reasons for these discrepancies could be several fold. One problem may lie in the samples used to assess psychopathology associated with weight gain. Many studies (e.g., Perelberg, 1978; Pomerantz et al., 1977) utilized subjects who were currently receiving treatment for obesity. It can be argued that individuals in treatment may not be representative and may be more likely to present problems of mental health than a sample more representative of the obese population as a whole. Evidence for this conclusion comes from Prather & Williamson (1988) who compared obese subjects with a variety of other subject groups, including a group of obese subjects not in treatment. The obese sample seeking treatment reported higher levels of depression (Beck Depression Inventory) and psychopathology (MMPI), while the non-clinical obese sample displayed no more depression nor psychopathology relative to a non-clinical, normal-weight control group. A precise determination of the relationship between obesity and mental health may also have been hampered by the lack of prospective studies that have tracked the same individuals over time, to determine if changes in weight status predict changes in psychosocial functioning. The vast majority of studies has utilized crosssectional designs, assessing psychosocial functioning at one point in individuals who were currently obese. Such a design does not allow for a determination of the relationship between weight change and changes in psychosocial functioning. A more precise measure of such a relationship is the prospective study. If changes in weight status are related to changes in psychosocial functioning, one would predict that an individual who experiences a weight change would also experience a significant change in measures of this area of functioning. Thus, the purpose of the current study was to analyse, in a prospective manner, the relationship between changes in body weight and changes in psychosocial functioning in men and women. While more global levels of psychosocial functioning have not been previously reported in cross-sectional studies (Klesges, 1984) it has been theorized, and even advocated, that obese subjects suffer generalized (global) problems in psychosocial functioning (e.g., Banis et al., 1988; Hudson & Williams, 1981). Because only longitudinal investigations can adequately evaluate changes in psychosocial functioning as it relates to changes in body weight, the current study evaluated measures thought to be sensitive to changes in body weight: namely, depression, marital satisfaction, and family functioning.
147
WEIGHT CHANGE, PSYCHOSOCIALFUNCTIONING METHOD Subjects
At baseline, 399 Caucasian adults (204 males, 195 non-pregnant females) were recruited as part of a larger longitudinal study of cardiovascular risk factors. Average initial age of participants was 33.7 years (SD = 4.5). As Table 1 indicates, average initial weight for males was 192.21b (SD=35.3) with 8.8% considered underweight and 35.3% considered overweight. Females’ average baseline weight was 148.8 lb (SD=32*8) with 23.6% of the sample considered underweight and 29.2% of the sample considered overweight, according to the Department of Health and Human Services norms using ~25th percentile of body mass index (kg/m’) as underweight and over the 75th percentile of body mass index as overweight (US DHHS, 1987). There was loss to attrition in the cohort of 14% from baseline. In addition, 11% did not return the psychosocial questionnaires, despite repeated efforts to secure this information. The resultant sample with complete 1 year from baseline was 297. Dropouts differed from study completers on baseline psychosocial measures. Although frequency of dropout by relative weight status was not significant [X2(2) = 1.3, p=O.52], there were significant drop status by relative weight status interactions on the psychosocial measures. As seen in Table 2, these interactions were significant for the Dyadic Adjustment Survey, Family Relationship Index, and the Family Adaptability and Cohesion Environment Scale (p
The Relationship Between Changes in Body Weight Changes in Psychosocial Functioning ROBERT
C. KLESGES
and MARY
and
L. KLEM
Center for Applied Psychological Research, Memphis State University
LISA M. KLESGES Department of Biostatistics and Epidemiology, University of Tennessee, Memphis
Previous studies have indicated that obesity is related to a variety of psychosocial problems. Unfortunately, the literature on the relationship between weight status and psychosocial functioning has primarily utilized clinical samples and crosssectional designs. The current study prospectively explored the relationship between weight gain and changes in psychosocial functioning. Subjects were 195 women and 204 men recruited as part of a larger longitudinal study of cardiovascular risk factors, who attended assessment sessions once per year for 2 consecutive years. Psychosocial functioning was assessed using the Dyadic Adjustment Scale (DAS), the Family Environment Scale (FES) and the Family Adaptability and Cohesion Scale 3rd Edition (FACES-III). Subjects were categorized based on their weight status at each year so the effect of a change in weight status on changes in psychosocial functioning could he evaluated. Multivariate measures indicated no changes in psychosocial functioning as a result of change in weight status over a l-year period for either men or women. It appears that shifts in body weight, at least in a sample of subjects with generally good levels of psychological functioning, are not associated with changes in the measured levels of psychosocial functioning.
INTRODUCTION
There is considerable agreement among health professionals regarding the negative health consequences of obesity. Although the precise nature of the relationship between obesity and health is unclear, obesity is clearly related to a higher-than-average risk of coronary heart disease (Van Itallie, 1979), as well as increased occurrence of hypertension, diabetes, arthritis and operative risk (Andres, 1980; Bray, 1976; Keys, 1980). In contrast, the relationship between obesity and psychological health is much less clear. Several investigations have suggested that, when compared to nortnalweight individuals, obese persons are more self-dissatisfied, emotionally unstable,
Address correspondence to: Robert C. Klesges, Center for Applied Psychological Research, Department of Psychology, Memphis State University, Memphis, TN 38120, U.S.A. This study was supported by two grants awarded to the first author (HL36553; HL-39332) by the National Heart, Lung, and Blood Institute. Support was also received from a Centers of Excellence grant awarded to the Department of Psychology, Memphis State University, by the state of Tennessee. 01956663/92/050145+09
$OS.OO/O
0 1992 Academic Press Limited
146
R. C. KLESGES ET AL.
apprehensive, passive, non-assertive and depressed (e.g., Hudson & Williams, 1981; Noppa & Hallstrom, 1981; Perelberg, 1978; Pluchik, 1976; Pomerantz et al., 1977). Other studies have concluded that obese individuals are likely to score lower than normal-weight individuals on measures of achievement, affiliation, personal adjustment as well as on measures of family functioning and marital satisfaction (e.g., Banis et al., 1988; Beck & Terry, 1985; Bradley, 1985; Waring, 1983; Wunderlich et al., 1973). An equal number of studies, however, have failed to find a relationship between obesity and these aspects of mental health. For example, Keith & Vanderber (1974) found no differences between obese and normal-weight subjects on an inventory of global personality characteristics, while Segers & Mertens (1974) found obese males to have scores lower than normal-weight and thin males on a measure of depression (indicating a lesser degree of depression). Likewise, Klesges (1984) also found no differences between obese and normal-weight subjects on global measures of depression, assertiveness and self-consciousness. The reasons for these discrepancies could be several fold. One problem may lie in the samples used to assess psychopathology associated with weight gain. Many studies (e.g., Perelberg, 1978; Pomerantz et al., 1977) utilized subjects who were currently receiving treatment for obesity. It can be argued that individuals in treatment may not be representative and may be more likely to present problems of mental health than a sample more representative of the obese population as a whole. Evidence for this conclusion comes from Prather & Williamson (1988) who compared obese subjects with a variety of other subject groups, including a group of obese subjects not in treatment. The obese sample seeking treatment reported higher levels of depression (Beck Depression Inventory) and psychopathology (MMPI), while the non-clinical obese sample displayed no more depression nor psychopathology relative to a non-clinical, normal-weight control group. A precise determination of the relationship between obesity and mental health may also have been hampered by the lack of prospective studies that have tracked the same individuals over time, to determine if changes in weight status predict changes in psychosocial functioning. The vast majority of studies has utilized crosssectional designs, assessing psychosocial functioning at one point in individuals who were currently obese. Such a design does not allow for a determination of the relationship between weight change and changes in psychosocial functioning. A more precise measure of such a relationship is the prospective study. If changes in weight status are related to changes in psychosocial functioning, one would predict that an individual who experiences a weight change would also experience a significant change in measures of this area of functioning. Thus, the purpose of the current study was to analyse, in a prospective manner, the relationship between changes in body weight and changes in psychosocial functioning in men and women. While more global levels of psychosocial functioning have not been previously reported in cross-sectional studies (Klesges, 1984) it has been theorized, and even advocated, that obese subjects suffer generalized (global) problems in psychosocial functioning (e.g., Banis et al., 1988; Hudson & Williams, 1981). Because only longitudinal investigations can adequately evaluate changes in psychosocial functioning as it relates to changes in body weight, the current study evaluated measures thought to be sensitive to changes in body weight: namely, depression, marital satisfaction, and family functioning.
147
WEIGHT CHANGE, PSYCHOSOCIALFUNCTIONING METHOD Subjects
At baseline, 399 Caucasian adults (204 males, 195 non-pregnant females) were recruited as part of a larger longitudinal study of cardiovascular risk factors. Average initial age of participants was 33.7 years (SD = 4.5). As Table 1 indicates, average initial weight for males was 192.21b (SD=35.3) with 8.8% considered underweight and 35.3% considered overweight. Females’ average baseline weight was 148.8 lb (SD=32*8) with 23.6% of the sample considered underweight and 29.2% of the sample considered overweight, according to the Department of Health and Human Services norms using ~25th percentile of body mass index (kg/m’) as underweight and over the 75th percentile of body mass index as overweight (US DHHS, 1987). There was loss to attrition in the cohort of 14% from baseline. In addition, 11% did not return the psychosocial questionnaires, despite repeated efforts to secure this information. The resultant sample with complete 1 year from baseline was 297. Dropouts differed from study completers on baseline psychosocial measures. Although frequency of dropout by relative weight status was not significant [X2(2) = 1.3, p=O.52], there were significant drop status by relative weight status interactions on the psychosocial measures. As seen in Table 2, these interactions were significant for the Dyadic Adjustment Survey, Family Relationship Index, and the Family Adaptability and Cohesion Environment Scale (p
