BrifishJournal oJUro1og.v (1992), 69, 46&464
01992 British Journal of Urology
Psychological Factors in Recurrent Uncomplicated Urinary Tract Infection J E N N I F E R C. HUNTand G L E N N WALLER Department of Clinical Psychology, Wigan District Health Authority; Department of Psychiatry, University of Manchester
Summary-Recurrent urinary tract infection (UTI) is a very common medical complaint among women. A large proportion of such recurrence is attributable to a small sub-group of sufferers. Medical factors have proven insufficient to explain all such cases, and a number of psychological factors have been suggested as having a causal role. This study examines the evidence for the effects of behavioural and personality factors. Neuroticism and specific "risky" behaviours are identified as particularly important, being related to both the diagnosis of recurrent UTI and the frequency of infection. These findings suggest that treatment of recurrent, intractable UTI might include a psychological component.
It is widely recognised that urinary tract infection 1988). However, it is clear that the mechanisms (UTI) is one of the most common infectious diseases leading to recurrent bacteriuria are not yet fully encountered in medical practice and that it is a explained (Fihn and Stamm, 1985). Attempts to source of frequent G P consultations (Andriole, treat recurrent UTI within a model of acute 1987). UTI is characterised by significant bacterial infection will inevitably meet with limited success colonisation of the bladder and is marked by until this understanding is increased. Such women dysuria and by frequency and urgency of mictura- often receive long-term antibiotic treatment, even tion. Estimates suggest that 20% of women will .though this has a number of possible side effects, experience UTI symptoms in any year and that half such as eventual resistance to the specific drug used of these will seek medical help (Sanford, 1975). (Vosti, 1975). In order to enhance knowledge of the causes of These figures are much lower in men, probably due to the protective barrier provided by their longer recurrent UTI, several behavioural and personality urethra (Bran et al., 1972). However, these overall factors have been investigated. These factors are incidence figures mask the fact that the number of generally seen as antecedents of UTI, encouraging UTIs is not distributed evenly among the sufferers. bacteria toenter and colonise the bladder. However, There appears to be a small group of recurrent UTI they might also be maintaining consequences of the suffererswho account for an unusually large number infection. There is some preliminary evidence to of reported cases. Mabeck (1972) estimated that suggest that these psychological factors can account one-sixth of sufferers account for 70% of recur- for some of the unexplained variance in the recurrence of UTI. rences. Several behavioural factors have been hypotheThe aetiological factors underlying recurrent UTI are still insufficiently understood. A number sised to enhance the risk of recurrent UTI (Galland of medical correlates are well established, such as et al., 1977; Adatto et al., 1979). Although the the role of bacterial adherence factors (Schaeffer, research concerning such factors and UTI is neither extensive nor sophisticated, particular behaviours appear to be relevant. They include low intake of liquid (Ervine et al., 1980), deferred voiding after Accepted for publication 31 May 1991 460
PSYCHOLOGICAL FACTORS IN RECURRENT UNCOMPLICATED URINARY TRACT INFECTION
the initial urge to urinate (Adatto el af., 1979), deferred voiding after sexual intercourse (Strom et al., 1987; Fihn, 1988), and frequency of intercourse (Foxman and Frerichs, 1985a). It is also frequently assumed that hygiene habits play a role in recurrence of UTIs, although the evidence for this factor is less substantial. Behavioural intervention studies are limited, but tend to confirm that changing the “risky” behaviours outlined above leads to a lower rate of recurrence of infection (Lumsden and Hyner, 1985). Research has shown that there are several major personality styles that are associated with recurrent UTI. These styles are within the normal range and do not necessarily reflect any psychiatric disorder. In particular, obsessionality and neuroticism have been described as relevant (Hafner et al., 1977; Rees and Farhoumand, 1977). However, these studies often lack appropriate comparison groups and generally use heterogeneous clinical subjects. In general, existing studies of psychological factors in the aetiology of recurrent UTI have major limitations. Existing research has generally used either idiosyncratic methodology or inappropriate groups for comparison (e.g. students, rather than a normal adult population). Given the results of preliminary studies of psychological intervention in this field of behavioural medicine (Lumsden and Hyner, 1985), it isobvious that more comprehensive psychological research could be of great value in understanding and treating recurrent UTI. This study considers such psychological factors in the presentation of recurrent UTI, examining behavioural and personality variables. It employs an appropriate clinical group (i.e. homogeneous in the diagnosis of recurrent UTI) and a more appropriate comparison group (i.e. suffering from a non-urinary tract infection and with no history of UTI).
Patients and Methods Two groups of subjects were recruited from a large General Practice. All 51 of the subjects who were initially approached were female and were selected through examination of a continuous series of laboratory reports. In the clinical group, the criteria for recurrent UTI were a positive current laboratory report and a history of at least 2 other such episodes in the past year. The current episode was required to have been defined by a laboratory report showing > los organisms/ml of urine. The previous episodes had been diagnosed by the medical practitioner. While
46 1
the great majority of these previous episodes were accompanied by laboratory reports, a small number were not. Any reported episode of UTI with a laboratory report that fell below the criterion of > los organisms/ml of urine was excluded from consideration. Using these criteria, the total number of urinary tract infections that the women had experienced in the previous year was also recorded. The comparison group were all suffering currently from non-urinary infections (throat infections, fungal infections, or digestive tract infections-confirmed by laboratory report) and had no history of urinary tract infection. The comparison women were also selected to match the marital status and age of the clinical group. The mean ages of the clinical group (mean = 36.5 years, SD = 9.57) and the comparison group (mean = 36.7 years, SD = 8.82) were very similar. However, these ages are substantially higher than the ages of the student populations studied by other researchers (Adatto et af.,1979). Subjects were interviewed to explain that they were being asked to assist with a study of psychological factors in general health, and to explain how to complete the questionnaires. They were asked to return the questionnaires by replypaid envelope within 7 days. The response rate was relatively high. Of the 25 women interviewed for the comparison group, 3 failed to return their questionnaires. Of the 26 women interviewed for the clinical group, 3 failed to return their questionnaires and 4 returns could not be scored because of missing data. Thus the clinical group consisted of 19 women with a confirmed history of recurrent UTI and the comparison group consisted of 22 women with no such history. The behavioural factors were measured using Foxman and Frerichs’s (1985b) “Inventory of Habits”. This self-report questionnaire contains items relating to behaviours that are assumed to provide some risk of developing urinary tract infection. For the present purposes, a sub-set of the most relevant behaviours was selected on the basis of previous research findings. These behaviours included frequency of urination (per 24 h); delay in urination after the initial urge; frequency of hesitation to excuse oneself from a social setting in order to urinate; frequency of sexual intercourse; frequency of urination within 30 min prior to sexual intercourse; frequency of urination within 15 min after sexual intercourse ; frequency of washing the vaginal area within 15 min after sexual intercourse; frequency of bathing. Frequency of showering was also recorded for the present study, using response
462 categories similar to those used by Foxman and Frerichs when enquiring about the frequency of bathing. The “Inventory of Habits” employs ordinal (ranked) responses, which are not suitable for parametric analysis. Therefore we used non-parametric methods for all statistical analyses involving these measures. More specifically, where the 2 groups were being compared on the Inventory scores, we used the Mann-Whitney test for independent samples. When the Inventory scores were being tested for association with the frequency of UTI, correlations were obtained using Kendall’s tau. These non-parametric analyses are detailed by Cohen and Holliday (1982). Relevant personality variables were also selected on the basis of the findings of previous research. The Maudsley Obsessive-Compulsive Inventory (MOC) (Rachman and Hodgson, 1980) was used to measure obsessionality, which was suggested to be relevant by Rees and Farhoumand (1977). The Eysenck Personality Questionnaire (EPQ) (Eysenck and Eysenck, 1975) was used to measure 2 features that had been suggested by previous research. First, it measures general neuroticism (EPQN), the role of which was highlighted by Hafner et al. (1977). Second, it measures extroversion and introversion (EPQE), a dimension that might encompass the tendencies towards “emotional repression” and “withdrawal” that Straub et al. (1949) suggested were relevant to disturbed bladder function. The EPQ also measures a third dimension of personality-psychoticism ( E P Q P h which is not hypothesised to be relevant to recurrent UTI. The EPQ and the MOC provide data that are suitable for parametric analyses. Therefore, comparison of the groups on personality measures is carried out using 1-way analysis of variance (ANOVA) for independent groups. The association of personality measures and the frequency of UTI is measured using Pearson’s product-moment correlation statistic (r).These parametric methods are detailed by Cohen and Holliday (1982). Results The data were considered in 2 ways. First, the qualitative link between psychological factors and a diagnosis of recurrent UTI was addressed by comparing the 2 groups. Second, the quantitative association between psychological factors and the frequency of UTI (in the recurrent UTI group only) was described.
BRITISH JOURNAL OF UROLOGY
Behaviouralfactors associated with diagnosis of recurrent UTI Table 1 shows the results of Mann-Whitney U tests, used to compare the responses of the clinical and comparison group on the different items of the Inventory of Habits. One-tailed tests were used because previous models and research led to the prediction that particular behavioural patterns (rather than general behavioural abnormality) would be associated with recurrent UTI. Table 1 Mean Ranks of Scores on Inventory, with Comparison of Groups Using 1-tailed Mann-Whitney Tests Clinical group
Frequency of urination Delay before urination Hesitation to excuse self to urinate Frequency of sexual intercourse Urination prior to sexual intercourse Urination following sexual intercourse Washing following sexual intercourse Frequency of bathing Frequency of showering
(n=19)
Comparison group (n=22)
2
P
19.6
22.3
0.749
NS
19.8
22.1
0.675
NS
20.4
20.6
0.057
NS
23.3
18.2
1.460
NS
24.1
17.6
1.841
0.04
20.8
19.3
0.409
NS
18.9
22.0
0.846
NS
17.7
23.8
1.756
0.04
22.2
20.0
0.623
NS
As can be seen, there was relatively little difference between the groups on most of the Inventory responses. However, there were reliable differences on 2 of the 9 behaviours. The clinical group were significantly more likely to urinate prior to sexual intercourse, and took fewer baths than the comparison women. Both behavioural differences were in the direction predicted from previous research. Personality factors associated with diagnosis of recurrent UTI Table 2 shows the mean scores of the 2 groups on the measures of personality, and the results of 1way ANOVAs comparing the groups’ scores. Again, 1-tailed tests were used for most of the comparisons because previous research suggests that the clinical group will be more obsessional, neurotic and introverted than the comparison
PSYCHOLOGICAL FACTORS IN RECURRENT UNCOMPLICATED URINARY TRACT INFECTION
Table 2 Mean Scores on Personality Measures, with Comparisonof Groups Using 1-tailedANOVAs Clinical (n=I9)
Comparison group (n=22) F
8.58 (4.69) 14.1 (4.15) 11.3 (5.13) 3.05 (1.96)
6.10 (4.27) 11.2 (5.89) 14.3 (3.16) 2.70 (1.38)
group
P
463
r = 0 . 3 9 ; P
01992 British Journal of Urology
Psychological Factors in Recurrent Uncomplicated Urinary Tract Infection J E N N I F E R C. HUNTand G L E N N WALLER Department of Clinical Psychology, Wigan District Health Authority; Department of Psychiatry, University of Manchester
Summary-Recurrent urinary tract infection (UTI) is a very common medical complaint among women. A large proportion of such recurrence is attributable to a small sub-group of sufferers. Medical factors have proven insufficient to explain all such cases, and a number of psychological factors have been suggested as having a causal role. This study examines the evidence for the effects of behavioural and personality factors. Neuroticism and specific "risky" behaviours are identified as particularly important, being related to both the diagnosis of recurrent UTI and the frequency of infection. These findings suggest that treatment of recurrent, intractable UTI might include a psychological component.
It is widely recognised that urinary tract infection 1988). However, it is clear that the mechanisms (UTI) is one of the most common infectious diseases leading to recurrent bacteriuria are not yet fully encountered in medical practice and that it is a explained (Fihn and Stamm, 1985). Attempts to source of frequent G P consultations (Andriole, treat recurrent UTI within a model of acute 1987). UTI is characterised by significant bacterial infection will inevitably meet with limited success colonisation of the bladder and is marked by until this understanding is increased. Such women dysuria and by frequency and urgency of mictura- often receive long-term antibiotic treatment, even tion. Estimates suggest that 20% of women will .though this has a number of possible side effects, experience UTI symptoms in any year and that half such as eventual resistance to the specific drug used of these will seek medical help (Sanford, 1975). (Vosti, 1975). In order to enhance knowledge of the causes of These figures are much lower in men, probably due to the protective barrier provided by their longer recurrent UTI, several behavioural and personality urethra (Bran et al., 1972). However, these overall factors have been investigated. These factors are incidence figures mask the fact that the number of generally seen as antecedents of UTI, encouraging UTIs is not distributed evenly among the sufferers. bacteria toenter and colonise the bladder. However, There appears to be a small group of recurrent UTI they might also be maintaining consequences of the suffererswho account for an unusually large number infection. There is some preliminary evidence to of reported cases. Mabeck (1972) estimated that suggest that these psychological factors can account one-sixth of sufferers account for 70% of recur- for some of the unexplained variance in the recurrence of UTI. rences. Several behavioural factors have been hypotheThe aetiological factors underlying recurrent UTI are still insufficiently understood. A number sised to enhance the risk of recurrent UTI (Galland of medical correlates are well established, such as et al., 1977; Adatto et al., 1979). Although the the role of bacterial adherence factors (Schaeffer, research concerning such factors and UTI is neither extensive nor sophisticated, particular behaviours appear to be relevant. They include low intake of liquid (Ervine et al., 1980), deferred voiding after Accepted for publication 31 May 1991 460
PSYCHOLOGICAL FACTORS IN RECURRENT UNCOMPLICATED URINARY TRACT INFECTION
the initial urge to urinate (Adatto el af., 1979), deferred voiding after sexual intercourse (Strom et al., 1987; Fihn, 1988), and frequency of intercourse (Foxman and Frerichs, 1985a). It is also frequently assumed that hygiene habits play a role in recurrence of UTIs, although the evidence for this factor is less substantial. Behavioural intervention studies are limited, but tend to confirm that changing the “risky” behaviours outlined above leads to a lower rate of recurrence of infection (Lumsden and Hyner, 1985). Research has shown that there are several major personality styles that are associated with recurrent UTI. These styles are within the normal range and do not necessarily reflect any psychiatric disorder. In particular, obsessionality and neuroticism have been described as relevant (Hafner et al., 1977; Rees and Farhoumand, 1977). However, these studies often lack appropriate comparison groups and generally use heterogeneous clinical subjects. In general, existing studies of psychological factors in the aetiology of recurrent UTI have major limitations. Existing research has generally used either idiosyncratic methodology or inappropriate groups for comparison (e.g. students, rather than a normal adult population). Given the results of preliminary studies of psychological intervention in this field of behavioural medicine (Lumsden and Hyner, 1985), it isobvious that more comprehensive psychological research could be of great value in understanding and treating recurrent UTI. This study considers such psychological factors in the presentation of recurrent UTI, examining behavioural and personality variables. It employs an appropriate clinical group (i.e. homogeneous in the diagnosis of recurrent UTI) and a more appropriate comparison group (i.e. suffering from a non-urinary tract infection and with no history of UTI).
Patients and Methods Two groups of subjects were recruited from a large General Practice. All 51 of the subjects who were initially approached were female and were selected through examination of a continuous series of laboratory reports. In the clinical group, the criteria for recurrent UTI were a positive current laboratory report and a history of at least 2 other such episodes in the past year. The current episode was required to have been defined by a laboratory report showing > los organisms/ml of urine. The previous episodes had been diagnosed by the medical practitioner. While
46 1
the great majority of these previous episodes were accompanied by laboratory reports, a small number were not. Any reported episode of UTI with a laboratory report that fell below the criterion of > los organisms/ml of urine was excluded from consideration. Using these criteria, the total number of urinary tract infections that the women had experienced in the previous year was also recorded. The comparison group were all suffering currently from non-urinary infections (throat infections, fungal infections, or digestive tract infections-confirmed by laboratory report) and had no history of urinary tract infection. The comparison women were also selected to match the marital status and age of the clinical group. The mean ages of the clinical group (mean = 36.5 years, SD = 9.57) and the comparison group (mean = 36.7 years, SD = 8.82) were very similar. However, these ages are substantially higher than the ages of the student populations studied by other researchers (Adatto et af.,1979). Subjects were interviewed to explain that they were being asked to assist with a study of psychological factors in general health, and to explain how to complete the questionnaires. They were asked to return the questionnaires by replypaid envelope within 7 days. The response rate was relatively high. Of the 25 women interviewed for the comparison group, 3 failed to return their questionnaires. Of the 26 women interviewed for the clinical group, 3 failed to return their questionnaires and 4 returns could not be scored because of missing data. Thus the clinical group consisted of 19 women with a confirmed history of recurrent UTI and the comparison group consisted of 22 women with no such history. The behavioural factors were measured using Foxman and Frerichs’s (1985b) “Inventory of Habits”. This self-report questionnaire contains items relating to behaviours that are assumed to provide some risk of developing urinary tract infection. For the present purposes, a sub-set of the most relevant behaviours was selected on the basis of previous research findings. These behaviours included frequency of urination (per 24 h); delay in urination after the initial urge; frequency of hesitation to excuse oneself from a social setting in order to urinate; frequency of sexual intercourse; frequency of urination within 30 min prior to sexual intercourse; frequency of urination within 15 min after sexual intercourse ; frequency of washing the vaginal area within 15 min after sexual intercourse; frequency of bathing. Frequency of showering was also recorded for the present study, using response
462 categories similar to those used by Foxman and Frerichs when enquiring about the frequency of bathing. The “Inventory of Habits” employs ordinal (ranked) responses, which are not suitable for parametric analysis. Therefore we used non-parametric methods for all statistical analyses involving these measures. More specifically, where the 2 groups were being compared on the Inventory scores, we used the Mann-Whitney test for independent samples. When the Inventory scores were being tested for association with the frequency of UTI, correlations were obtained using Kendall’s tau. These non-parametric analyses are detailed by Cohen and Holliday (1982). Relevant personality variables were also selected on the basis of the findings of previous research. The Maudsley Obsessive-Compulsive Inventory (MOC) (Rachman and Hodgson, 1980) was used to measure obsessionality, which was suggested to be relevant by Rees and Farhoumand (1977). The Eysenck Personality Questionnaire (EPQ) (Eysenck and Eysenck, 1975) was used to measure 2 features that had been suggested by previous research. First, it measures general neuroticism (EPQN), the role of which was highlighted by Hafner et al. (1977). Second, it measures extroversion and introversion (EPQE), a dimension that might encompass the tendencies towards “emotional repression” and “withdrawal” that Straub et al. (1949) suggested were relevant to disturbed bladder function. The EPQ also measures a third dimension of personality-psychoticism ( E P Q P h which is not hypothesised to be relevant to recurrent UTI. The EPQ and the MOC provide data that are suitable for parametric analyses. Therefore, comparison of the groups on personality measures is carried out using 1-way analysis of variance (ANOVA) for independent groups. The association of personality measures and the frequency of UTI is measured using Pearson’s product-moment correlation statistic (r).These parametric methods are detailed by Cohen and Holliday (1982). Results The data were considered in 2 ways. First, the qualitative link between psychological factors and a diagnosis of recurrent UTI was addressed by comparing the 2 groups. Second, the quantitative association between psychological factors and the frequency of UTI (in the recurrent UTI group only) was described.
BRITISH JOURNAL OF UROLOGY
Behaviouralfactors associated with diagnosis of recurrent UTI Table 1 shows the results of Mann-Whitney U tests, used to compare the responses of the clinical and comparison group on the different items of the Inventory of Habits. One-tailed tests were used because previous models and research led to the prediction that particular behavioural patterns (rather than general behavioural abnormality) would be associated with recurrent UTI. Table 1 Mean Ranks of Scores on Inventory, with Comparison of Groups Using 1-tailed Mann-Whitney Tests Clinical group
Frequency of urination Delay before urination Hesitation to excuse self to urinate Frequency of sexual intercourse Urination prior to sexual intercourse Urination following sexual intercourse Washing following sexual intercourse Frequency of bathing Frequency of showering
(n=19)
Comparison group (n=22)
2
P
19.6
22.3
0.749
NS
19.8
22.1
0.675
NS
20.4
20.6
0.057
NS
23.3
18.2
1.460
NS
24.1
17.6
1.841
0.04
20.8
19.3
0.409
NS
18.9
22.0
0.846
NS
17.7
23.8
1.756
0.04
22.2
20.0
0.623
NS
As can be seen, there was relatively little difference between the groups on most of the Inventory responses. However, there were reliable differences on 2 of the 9 behaviours. The clinical group were significantly more likely to urinate prior to sexual intercourse, and took fewer baths than the comparison women. Both behavioural differences were in the direction predicted from previous research. Personality factors associated with diagnosis of recurrent UTI Table 2 shows the mean scores of the 2 groups on the measures of personality, and the results of 1way ANOVAs comparing the groups’ scores. Again, 1-tailed tests were used for most of the comparisons because previous research suggests that the clinical group will be more obsessional, neurotic and introverted than the comparison
PSYCHOLOGICAL FACTORS IN RECURRENT UNCOMPLICATED URINARY TRACT INFECTION
Table 2 Mean Scores on Personality Measures, with Comparisonof Groups Using 1-tailedANOVAs Clinical (n=I9)
Comparison group (n=22) F
8.58 (4.69) 14.1 (4.15) 11.3 (5.13) 3.05 (1.96)
6.10 (4.27) 11.2 (5.89) 14.3 (3.16) 2.70 (1.38)
group
P
463
r = 0 . 3 9 ; P
