Journal Article Annotations
2023, 4th Quarter

Suicide

Annotations by Sharvari Shivanekar, MD.
January, 2024

All-Cause and Cause-Specific Mortality Among Individuals With Hypochondriasis.

PUBLICATION #1 — Suicide

All-Cause and Cause-Specific Mortality Among Individuals With Hypochondriasis.

David Mataix-Cols, Kayoko Isomura, Anna Sidorchuk, Daniel Rautio, Volen Z Ivanov, Christian Rück, Susanna Österman, Paul Lichtenstein, Henrik Larsson, Ralf Kuja-Halkola, Zheng Chang, Isabell Brickel, Erik Hedman-Lagerlöf, Lorena Fernández de la Cruz

Abstract: JAMA Psychiatry. 2023 Dec 13:e234744. doi: 10.1001/jamapsychiatry.2023.4744. Online ahead of print.

Importance:
Hypochondriasis, also known as health anxiety disorder, is a prevalent, yet underdiagnosed psychiatric disorder characterized by persistent preoccupation about having serious and progressive physical disorders. The risk of mortality among individuals with hypochondriasis is unknown.

Objective:
To investigate all-cause and cause-specific mortality among a large cohort of individuals with hypochondriasis.

Design, setting, and participants:
This Swedish nationwide matched-cohort study included 4129 individuals with a validated International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) diagnosis of hypochondriasis assigned between January 1, 1997, and December 31, 2020, and 41 290 demographically matched individuals without hypochondriasis. Individuals with diagnoses of dysmorphophobia (body dysmorphic disorder) assigned during the same period were excluded from the cohort. Statistical analyses were conducted between May 5 and September 27, 2023.

Exposure:
Validated ICD-10 diagnoses of hypochondriasis in the National Patient Register.

Main outcome and measures:
All-cause and cause-specific mortality in the Cause of Death Register. Covariates included birth year, sex, county of residence, country of birth (Sweden vs abroad), latest recorded education, civil status, family income, and lifetime psychiatric comorbidities. Stratified Cox proportional hazards regression models were used to estimate the hazard ratios (HRs) and 95% CIs of all-cause and cause-specific mortality.

Results:
Of the 4129 individuals with hypochondriasis (2342 women [56.7%]; median age at first diagnosis, 34.5 years [IQR, 26.3-46.1 years]) and 41 290 demographically matched individuals without hypochondriasis (23 420 women [56.7%]; median age at matching, 34.5 years [IQR, 26.4-46.2 years]) in the study, 268 individuals with hypochondriasis and 1761 individuals without hypochondriasis died during the study period, corresponding to crude mortality rates of 8.5 and 5.5 per 1000 person-years, respectively. In models adjusted for sociodemographic variables, an increased rate of all-cause mortality was observed among individuals with hypochondriasis compared with individuals without hypochondriasis (HR, 1.69; 95% CI, 1.47-1.93). An increased rate was observed for both natural (HR, 1.60; 95% CI, 1.38-1.85) and unnatural (HR, 2.43; 95% CI, 1.61-3.68) causes of death. Most deaths from unnatural causes were attributed to suicide (HR, 4.14; 95% CI, 2.44-7.03). The results were generally robust to additional adjustment for lifetime psychiatric disorders.

Conclusions and relevance:
This cohort study suggests that individuals with hypochondriasis have an increased risk of death from both natural and unnatural causes, particularly suicide, compared with individuals from the general population without hypochondriasis. Improved detection and access to evidence-based care should be prioritized.

Annotation

The finding:
This large Swedish matched-cohort study illustrates a paradox, whereby individuals with an ICD-10 diagnosis of hypochondriasis (also known as health/illness anxiety disorder) have an increased risk of death despite their pervasive fears of illness and death. The researchers found that people with the diagnosis have an increased risk of death from both natural and unnatural causes, particularly suicide. In the study, the risk of suicide was more than four times higher for those diagnosed with hypochondriasis compared to the general population.

Strength and weaknesses:
This study was both the largest study of individuals with clinically diagnosed hypochondriasis ever done, and the first study to examine the causes of death in this population. Strengths include a large nationwide cohort, mean follow up time of nearly eight years, adjustment for important sociodemographic variables and lifetime psychiatric comorbidities. Some limitations include hypochondriasis being underdiagnosed in Sweden, thus underestimating the excess mortality in these individuals. Data from primary care was not included, nor was an adjustment made for somatization disorder.

Relevance:
C-L psychiatrists should be aware of the increased risk of suicide in this population. This is particularly true if the patient has a lifetime history of depression and anxiety, and this risk remains statistically significant even after systematic adjustment for lifetime psychiatric disorders. This study illustrates the importance of thorough lethality risk assessment in these individuals who are often dismissed by health professionals and bear the burden of a highly stigmatized diagnosis.