Variation in somatic symptoms by patient health questionnaire-9 depression scores in a representative Japanese sample

BackgroundThis study aims to evaluate variation in somatic symptoms by age using patient health questionnaire-9 (PHQ) depression scores, which may be helpful in identifying depression.MethodsThe study evaluated a nationally representative cross-sectional sample of community-dwelling adults in Japan in 2013. We utilized the PHQ to identify risk for depression, with PHQ10 defining at least moderate depression. Bivariate and factor analyses were used to capture underlying patterns in self-reported symptoms over a 30day period; aged-stratified multivariate logistic regression was performed to further explore associations between age, symptoms, and depression.ResultsOf 3753 respondents, 296 (8, 95% CI 7.0-8.8) reported a PHQ10; 42% of these were male and mean age was 51.7years old (SD=18.6). Multivariate analysis showed that presence of fatigue and malaise (OR=1.7, 95% CI 1.3-2.4) was significantly associated with PHQ10. After stratification by age, PHQ10 was associated with gastrointestinal complaints among 18-39year olds (OR=1.7, 95% CI 1.0-2.9); fatigue and malaise (OR=1.8, 95% CI 1.1-3.1) among 40-64year olds; and fatigue and malaise (OR=1.8, 95% CI 1.1-3.0) as well as extremity pain (OR=1.7, 95% CI 1.0-2.8) in over 65year olds.ConclusionAge-related somatic symptom correlates of PHQ10 differ across the lifespan. Predominantly gastrointestinal symptoms in younger patients, and generalized fatigue, malaise, and musculoskeletal pain in older groups were observed. In order for screening physicians to proactively identify depression, awareness of age-related somatic symptoms is warranted.