Association between Mental Disorders and Subsequent Medical Conditions.

BACKGROUND: Persons with mental disorders are at a higher risk than the general population for the subsequent development of certain medical conditions. METHODS: We used a population-based cohort from Danish national registries that included data on more than 5.9 million persons born in Denmark from 1900 through 2015 and followed them from 2000 through 2016, for a total of 83.9 million person-years. We assessed 10 broad types of mental disorders and 9 broad categories of medical conditions (which encompassed 31 specific conditions). We used Cox regression models to calculate overall hazard ratios and time-dependent hazard ratios for pairs of mental disorders and medical conditions, after adjustment for age, sex, calendar time, and previous mental disorders. Absolute risks were estimated with the use of competing-risks survival analyses. RESULTS: A total of 698,874 of 5,940,299 persons (11.8%) were identified as having a mental disorder. The median age of the total population was 32.1 years at entry into the cohort and 48.7 years at the time of the last follow-up. Persons with a mental disorder had a higher risk than those without such disorders with respect to 76 of 90 pairs of mental disorders and medical conditions. The median hazard ratio for an association between a mental disorder and a medical condition was 1.37. The lowest hazard ratio was 0.82 for organic mental disorders and the broad category of cancer (95% confidence interval [CI], 0.80 to 0.84), and the highest was 3.62 for eating disorders and urogenital conditions (95% CI, 3.11 to 4.22). Several specific pairs showed a reduced risk (e.g., schizophrenia and musculoskeletal conditions). Risks varied according to the time since the diagnosis of a mental disorder. The absolute risk of a medical condition within 15 years after a mental disorder was diagnosed varied from 0.6% for a urogenital condition among persons with a developmental disorder to 54.1% for a circulatory disorder among those with an organic mental disorder. CONCLUSIONS: Most mental disorders were associated with an increased risk of a subsequent medical condition; hazard ratios ranged from 0.82 to 3.62 and varied according to the time since the diagnosis of the mental disorder. (Funded by the Danish National Research Foundation and others; COMO-GMC ClinicalTrials.gov number, NCT03847753.).

The Significance of Depression for Short-term Readmission and Mortality After a Pneumonia Admission.

BACKGROUND: Depression is highly prevalent among hospitalized patients with pneumonia. At discharge, these patients transfer to a less care-intensive home-based setting. Nevertheless, little is known on the prognosis in the postdischarge period. OBJECTIVE: The objective of this study was to investigate the influence of depression on 30-day mortality and readmission in persons discharged after a pneumonia admission. DESIGN: This was a population-based cohort study using the Danish registries. SUBJECTS: All persons aged 50+ years with a pneumonia admission in 2000-2016 in Denmark. MEASURES: Mortality rate ratios for 30-day mortality and incidence rate ratios for 30-day readmission in pneumonia patients with versus without depression. RESULTS: We identified 379,265 pneumonia admissions, hereof 83,257 (22.0%) with depression. The overall adjusted mortality rate ratio was 1.29 (95% confidence interval: 1.25-1.33), and the overall adjusted incidence rate ratio was 1.07 (95% confidence interval: 1.05-1.08). The mortality risk was higher for all ages and throughout the 30-day period in persons with versus without depression. This risk was modified by sociodemographic and socioeconomic characteristics (excluding sex and education), admission-related factors, comorbidities, and use of benzodiazepines, opioids, or antipsychotics. The readmission risk was higher until age 90 and tended to be higher throughout the 30-day period. This risk was modified by age, cohabitation, residency, admission-related factors, comorbidities, and use of opioids or antipsychotics. For both outcomes, the relative effect of depression was highest among the youngest, among those with a short hospital stay and among those with few comorbidities. CONCLUSION: Depression is an independent risk factor for 30-day mortality and readmission in persons who transfer from hospital care to home-based care.

Depression and Uptake of Oral Anticoagulation Therapy in Patients With Atrial Fibrillation: A Danish Nationwide Cohort Study.

BACKGROUND: Oral anticoagulation therapy (OAT) in patients with atrial fibrillation (AF) is a highly important preventive intervention, perhaps especially in those with comorbid depression, who have a worse prognosis. However, OAT may pose particular challenges in depressed patients. OBJECTIVES: To assess whether AF patients with depression have lower OAT uptake. METHODS: This nationwide register-based 2005-2016 cohort study of all Danes with AF and OAT indication (CHA2DS2VASc stroke risk score ≥2) assessed OAT initiation within 90 days in those with incident AF (N=147,162) and OAT prevalence in those with prevalent AF (N=192,656). The associations of depression with both outcomes were estimated in regression analyses with successive adjustment for socioeconomic characteristics and somatic and psychiatric comorbidity. RESULTS: Comorbid depression was significantly associated with lower frequency of OAT initiation in incident AF patients {adjusted proportion differences (aPDs): -6.6% [95% confidence interval (CI), -7.4 to -5.9]} and lower prevalence of OAT [aPD: -4.2% (95% CI, -4.7 to -3.8)] in prevalent AF patients. Yet, the OAT uptake increased substantially during the period, particularly in depressed patients [aPD for OAT prevalence in 2016: -0.8% (95% CI, -1.6 to -0.0)]. CONCLUSIONS: Comorbid depression was associated with a significantly lower OAT uptake in patients with AF, which questions whether depressed patients receive sufficient support to manage this consequential cardiac condition. However, a substantial increase in the overall OAT uptake and a decrease of the depression-associated deficit in OAT were seen over the period during which OAT was developed through the introduction of new oral anticoagulation therapy.

Perceived Stress, Multimorbidity, and Risk for Hospitalizations for Ambulatory Care-sensitive Conditions: A Population-based Cohort Study.

BACKGROUND: Psychiatric disorders are associated with an increased risk for ambulatory care-sensitive condition (ACSC)-related hospitalizations, but it remains unknown whether this holds for individuals with nonsyndromic stress that is more prevalent in the general population. OBJECTIVES: To determine whether perceived stress is associated with ACSC-related hospitalizations and rehospitalizations, and posthospitalization 30-day mortality. RESEARCH DESIGN AND MEASURES: Population-based cohort study with 118,410 participants from the Danish National Health Survey 2010, which included data on Cohen's Perceived Stress Scale, followed from 2010 to 2014, combined with individual-level national register data on hospitalizations and mortality. Multimorbidity was assessed using health register information on diagnoses and drug prescriptions within 39 condition categories. RESULTS: Being in the highest perceived stress quintile was associated with a 2.13-times higher ACSC-related hospitalization risk (95% CI, 1.91, 2.38) versus being in the lowest stress quintile after adjusting for age, sex, follow-up time, and predisposing conditions. The associated risk attenuated to 1.48 (95% CI, 1.32, 1.67) after fully adjusting for multimorbidity and socioeconomic factors. Individuals with above reference stress levels experienced 1703 excess ACSC-related hospitalizations (18% of all). A dose-response relationship was observed between perceived stress and the ACSC-related hospitalization rate regardless of multimorbidity status. Being in the highest stress quintile was associated with a 1.26-times insignificantly increased adjusted risk (95% CI, 0.79, 2.00) for ACSC rehospitalizations and a 1.43-times increased adjusted risk (95% CI, 1.13, 1.81) of mortality within 30 days of admission. CONCLUSIONS: Elevated perceived stress levels are associated with increased risk for ACSC-related hospitalization and poor short-term prognosis.

Serious Mental Illness and Risk for Hospitalizations and Rehospitalizations for Ambulatory Care-sensitive Conditions in Denmark: A Nationwide Population-based Cohort Study.

BACKGROUND: Hospitalizations for ambulatory care-sensitive conditions (ACSCs) and early rehospitalizations increase health care costs. OBJECTIVES: To determine if individuals with serious mental illnesses (SMIs) (eg, schizophrenia or bipolar disorder) are at increased risk for hospitalizations for ACSCs, and rehospitalization for the same or another ACSC, within 30 days. RESEARCH DESIGN: Population-based cohort study. PARTICIPANTS: A total of 5.9 million Danish persons aged 18 years and older between January 1, 1999 and December 31, 2013. MEASURES: The Danish Psychiatric Central Register provided information on SMI diagnoses and the Danish National Patient Register on hospitalizations for ACSCs and 30-day rehospitalizations. RESULTS: SMI was associated with increased risk for having any ACSC-related hospitalization after adjusting for demographics, socioeconomic factors, comorbidities, and prior primary care utilization [incidence rate ratio (IRR): 1.41; 95% confidence interval (95% CI), 1.37-1.45]. Among individual ACSCs, SMI was associated with increased risk for hospitalizations for angina (IRR: 1.14, 95% CI, 1.04-1.25), chronic obstructive pulmonary disease/asthma exacerbation (IRR: 1.87; 95% CI, 1.74-2.00), congestive heart failure exacerbation (IRR: 1.25; 95% CI, 1.16-1.35), and diabetes (IRR: 1.43; 95% CI, 1.31-1.57), appendiceal perforation (IRR: 1.49; 95% CI, 1.30-1.71), pneumonia (IRR: 1.72; 95% CI, 1.66-1.79), and urinary tract infection (IRR: 1.70; 95% CI, 1.62-1.78). SMI was also associated with increased risk for rehospitalization within 30 days for the same (IRR: 1.28; 95% CI, 1.18-1.40) or for another ACSC (IRR: 1.62; 95% CI, 1.49-1.76). CONCLUSION: Persons with SMI are at increased risk for hospitalizations for ACSCs, and after discharge, are at increased risk for rehospitalizations for ACSCs within 30 days.

Factors Associated With 30-Day Rehospitalization and Mortality in Older Patients After a Pneumonia Admission.

OBJECTIVES: Short-term rehospitalization and mortality are common events in older patients after a pneumonia admission, yet little knowledge exists on how to identify the patients at risk of these events. This knowledge is needed to ensure that health care attention is given to those with the highest needs. We therefore aimed to identify factors of importance for short-term rehospitalization and mortality in older patients after admission for pneumonia. DESIGN: Population-based cohort study. SETTING: The Danish nationwide registries. PARTICIPANTS: In total, 246,245 individuals aged 65-99 years who experienced 298,564 admissions for pneumonia from 2000 to 2016. METHODS: The explored factors in patients were demographic characteristics, health-seeking behavior, comorbidity, and medication use. A Cox proportional hazards model was used to calculate hazard ratios (HRs) for 30-day rehospitalization and 30-day mortality with 95% confidence intervals (CIs). RESULTS: Of the 298,564 admissions for pneumonia, 23.0% were rehospitalized and 8.1% died within 30 days of follow-up. Most of the investigated factors were significantly associated with these 2 outcomes. The HRs for rehospitalization ranged from 0.80 (95% CI 0.75-0.85) for old vs young age to 4.29 (95% CI 4.05-4.54) for many vs no prior admissions, whereas the HRs for mortality ranged from 0.87 (95% CI 0.83-0.91) for any vs no practical home care to 5.47 (95% CI 5.08-5.88) for old vs young age. Number of comorbidities, medications, and prior contacts to the health care system were associated with higher risk of both rehospitalization and mortality in a dose-response manner. CONCLUSIONS AND IMPLICATIONS: This study identified several potential factors of importance for short-term rehospitalization and mortality in older patients discharged after pneumonia. This knowledge can help physicians identify the patients with the highest need of care after admission for pneumonia, thus enabling efficient discharge planning and high-quality provision of care in primary care settings.

Depression, antidepressants, and the risk of non-valvular atrial fibrillation: A nationwide Danish matched cohort study.

BACKGROUND: Depression is associated with an increased risk of a series of cardiovascular diseases and with increased symptom burden in patients with atrial fibrillation. The aim of this study was to determine the association between depression as well as antidepressant treatment and the risk of incident atrial fibrillation. DESIGN: A nationwide register-based study comparing the atrial fibrillation risk in all Danes initiating antidepressant treatment from 2000 to 2013 ( N = 785,254) with that in a 1:5-matched sample from the general population. METHODS: Cox regression was used to estimate adjusted hazard ratios (aHRs) and associated 95% confidence intervals (95% CIs), both after initiation of treatment and in the month before when patients were assumed to have medically untreated depression. RESULTS: Antidepressant treatment was associated with a three-fold higher risk of atrial fibrillation during the first month (aHR = 3.18 (95% CI: 2.98-3.39)). This association gradually attenuated over the following year (aHR = 1.37 (95% CI: 1.31-1.44) 2-6 months after antidepressant therapy initiation, and aHR = 1.11 (95% CI: 1.06-1.16) 6-12 months after). However, the associated atrial fibrillation risk was even higher in the month before starting antidepressant treatment (aHR = 7.65 (95% CI: 7.05-8.30) from 30 to 15 days before, and aHR = 4.29 (95% CI: 3.94-4.67) the last 15 days before). Overall, 0.4% of patients were diagnosed with atrial fibrillation from 30 days before to 30 days after antidepressant treatment. CONCLUSIONS: Antidepressant users had a substantially increased atrial fibrillation risk, particularly before treatment initiation. Whether this mirrors a causal relation between depression and atrial fibrillation may have large consequences for public health and should be discussed.