Temporomandibular disorder-type pain and migraine headache in women: a preliminary twin study.

AIMS: To determine whether shared genetic influences are responsible for the association between pain from temporomandibular disorders (TMD) and migraine headache. METHODS: Data were obtained from 1,236 monozygotic and 570 dizygotic female twin pairs from the University of Washington Twin Registry. TMD pain was assessed with a question about persistent or recurrent pain in the jaw, temple, in front of the ear, or in the ear. The presence of migraine headache was determined by self-report of doctor-diagnosed migraine. Univariate and bivariate structural equation models estimated the components of variance attributable to genetic and environmental influences. RESULTS: The best fitting univariate models indicated that additive genetic effects contributed 27% of the variance in TMD pain (95% confidence interval = 15% to 38%) and 49% of the variance in migraine headache (95% confidence interval = 40% to 57%). The best-fitting bivariate model revealed that 12% of the genetic component of TMD pain is shared with migraine headache. CONCLUSION: These preliminary findings suggest that the association between TMD pain and migraine headache in women may be partially due to a modest shared genetic risk for both conditions. Future studies can focus on replicating these findings with symptom- and diagnosis-based instruments.

The prevalence of self-reported chronic fatigue in a U.S. twin registry.

OBJECTIVE: To investigate the prevalence and correlates of various definitions of self-reported lifetime fatiguing illness in a U.S. twin registry. METHODS: Data from 4591 female and male twins from the population-based Mid-Atlantic Twin Registry were available for this study. Variables representing different definitions of lifetime fatiguing illness and personal characteristics were obtained through questionnaires. Odds ratios and 95% confidence intervals were calculated as measures of association between fatigue and gender. Kaplan-Meier curves were produced to examine the age at onset for lifetime fatiguing illnesses. RESULTS: Prevalences for different definitions of self-reported lifetime fatigue ranged from 36.7% for any fatigue to 2.7% for chronic fatigue syndrome-like illness. Females were two to three times more likely to report fatigue than males. Gender differences increased as fatigue definitions grew more restrictive. Ages at onset of chronic fatiguing illness were significantly earlier and the number of ancillary symptoms was greater for females than males. People with lifetime fatigue had significantly more compromised functional status than people without lifetime fatigue. CONCLUSION: The prevalence of self-reported lifetime fatiguing illness varied widely depending upon how it was defined. Given the debilitating consequences of fatiguing illnesses, the reasons for the female predominance and the earlier onset in women should receive increased research priority.

Widespread Psychosocial Difficulties in Men and Women With Urologic Chronic Pelvic Pain Syndromes: Case-control Findings From the Multidisciplinary Approach to the Study of Chronic Pelvic Pain Research Network.

OBJECTIVE: To determine the extent, severity, and sex differences of psychosocial deficits in men and women with urologic chronic pelvic pain syndromes (UCPPS), which in the past have been considered separate bladder (interstitial cystitis-painful bladder syndrome) and prostate (chronic prostatitis-chronic pelvic pain syndrome) disorders. Evaluations of men and women separately suggest UCPPS is associated with increased anxiety and depression. However, studies directly testing deficits in broader psychosocial domains such as cognitive processes, intimate relationships, and trauma history, or tests of sex differences in the pattern of difficulties associated with UCPPS have not been performed. METHODS: A total of 233 female and 191 male UCPPS patients and 235 female and 182 male healthy controls (HCs) were recruited from 6 academic medical centers in the United States and evaluated with a comprehensive battery of symptom, psychosocial, and illness impact measures. Primary comparisons of interest were between UCPPS patients and HCs and between men and women with UCPPS. RESULTS: In addition to greater negative effect, male and female UCPPS patients show higher levels of current and lifetime stress, poorer illness coping, increased self-report of cognitive deficits, and more widespread pain symptoms compared with sex- and education-matched HCs. Similar problems were found in male and female UCPPS patients although female UCPPS patients showed increased self-report of childhood adversity and more widespread symptoms of pain and discomfort. CONCLUSION: Given the significance of psychosocial variables in prognosis and treatment of chronic pain conditions, the results add substantially to our understanding of the breath of difficulties associated with UCPPS and point to important areas for clinical assessment.