Risk of substance-related problems high in individuals with hypochondriasis

Individuals with hypochondriasis have a more than twofold increased risk of substance-related problems, according to a Swedish register-based matched cohort study.

The study included 4,129 individuals (mean age 37.68 years, 56.72 percent female) who received a diagnosis of hypochondriasis in specialist services and 41,290 demographically matched unexposed individuals (mean age 37.68 years, 56.72 percent female).

The outcome of substance-related problems was defined as alcohol and drug use disorders, dispensed medications for alcohol dependence and opioid use disorders, and alcohol- and drug-related accidental poisonings, deaths, and suspected criminal offenses.

Substance-related problems were identified in 504 individuals with hypochondriasis (12.2 percent) and 1,924 unexposed individuals (4.7 percent) over a mean follow-up of 6.8 and 7.5 years, respectively.

In multivariable Cox proportional hazards models, hypochondriasis was significantly associated with an increased risk of substance-related problems (HR, 2.55, 95 percent confidence interval [CI], 2.30–2.84). Similar results were obtained when analysis was limited to individuals without pre-existing substance-related problems (HR, 2.85, 95 percent CI, 2.48–3.27).

The risk estimates were attenuated after further adjustment for psychiatric comorbidity, particularly anxiety and depression, although the associations remained statistically significant.

Additional analysis that included primary care diagnoses of hypochondriasis (presumably reflecting less complex cases) yielded consistent results, with the risk of substance-related problems remaining elevated (HR, 1.61, 95 percent CI, 1.39–1.86).

The findings highlight the need for clinical vigilance regarding alcohol and drug use in this population.