Age and sex related self-reported symptoms in a general population across 30 years: Patterns of reporting and secular trend

OBJECTIVE: To study age and sex specific prevalence of 30 symptoms in random samples from the general population and to analyze possible secular trends across time. STUDY POPULATION: The study was based on data from eight on-going Swedish cohort studies, with baseline investigations performed between 1973 and 2003. Samples were drawn from the general population of the cities of Gothenburg and Eskilstuna, and of Uppsala County. Overall, 20,160 subjects were sampled, 14,470 (71.8%) responded, of whom 12.000 were unique subjects, and 2548 were part of more than one sample. METHODS: The Complaint score sub-scale of the Gothenburg Quality of Life instrument, listing 30 general symptoms was used. Responders were asked to indicate which symptoms they had experienced during the last three months. RESULTS: Women reported on average 7.8 symptoms, and men 5.3 (p<0.0001). Women reported higher prevalence than men for 24 of the 30 symptoms. In multivariate analyses four patterns of prevalence across age were identified in both men and women; increasing prevalence, decreasing, stable and biphasic prevalence. The symptoms in the various pattern groups differed somewhat between men and women. However, symptoms related to strain were prominent among symptoms decreasing with age. Moreover, there were secular trends. Across all symptoms reporting prevalence increased over time in men (p<0.001) as well as in women (p<0.0001). CONCLUSIONS: Women reported higher total symptom prevalence than men. Symptoms related to health generally increased with age, while symptoms related to stress decreased markedly. Significant secular trends across time regarding symptom prevalence were found.