Longterm persistence and nonrecurrence of depression treatment in Germany: a four‐year retrospective follow‐up using linked claims data

Objectives To measure persistence and nonrecurrence of depression treatment and investigate potential risk factors. Methods We retrospectively observed a closed cohort of insurees with new‐onset depression treatment in 2007 and without most psychiatric comorbidity for 16 quarters (plus one to ascertain discontinuation). We linked inpatient/outpatient/drug‐data per person and quarter. Person‐quarters containing specified depression services were classified as depression‐treatment‐person‐quarters (DTPQ). We defined longterm‐DTPQ‐persistence as 16 + 1 continuous DTPQ and longterm‐DTPQ‐nonrecurrence as 12 continuous quarters without DTPQ and used multivariate logistic regression to explore associations with these outcomes. Results Within first 16 quarters, 28,348 patients' first period (total time) persisted for a mean/median 5.4/3 (8.7/8) quarters. Fourteen percent had longterm‐DTPQ‐persistence , associated ( p  < .05) with baseline hospital (odds ratio, OR = 1.80), psychotherapy/specialist‐interview and antidepressants (OR = 1.81), age (years, OR = 1.03), unemployment (OR = 1.21), retirement (OR = 1.31), and insured as a dependent (OR = 1.32). Thirty‐four percent had longterm‐DTPQ‐nonrecurrence , associated with psychotherapy/specialist‐interview (OR = 1.40), antidepressants (OR = 0.54), female sex (OR = 0.84), age (years, OR = 0.99), retirement (OR = 1.18), and insured as a dependent (OR = 0.88). Women differed for episodic and not chronic treatment. Conclusion Treatment measures compared to survey's symptoms measures. We suggest further research on “treatment‐free‐time.” Antidepressants(−) and psychotherapy/specialist‐interview(+) were significantly associated with longterm‐DTPQ‐nonrecurrence . This was presumably moderated by possible short‐time/low‐dosage antidepressants use(−) and selective therapy assignment(+). Sample selectivity limited data misclassification.