Mental illness and health care use: a study among new neurological patients

We investigated 198 new neurological patients to learn if mental illness had an impact on nonpsychiatric health care use. Mental illness was assessed in a two-phase design, including the Schedules for Clinical Assessment in Neuropsychiatry (SCAN), providing ICD-10 diagnoses and two brief rating scales: the Symptom Check List (SCL-8) for anxiety and depression and the Whiteley-7 for somatization. The patients' use of health care was studied 5-10 years before and 18 months after the psychiatric assessment, using data from national patient registers. Mental illness was linked to data on health care use through weighted logistic regression. ICD-10 psychiatric disorders increased the risk of subsequent high use of nonpsychiatric hospital admissions - somatoform disorders with more than five times (OR=5.6; 95% CI=1.6-20.1) and anxiety/depression with almost four times (OR=3.7; 95% CI=1.1-12.0). There was also a trend, though less marked, linking mental illness to previous hospital use. Use of primary care was also markedly increased by mental disorders, however, only in patients entering the study as inpatients. In conclusion, neurological patients are at risk of being high users of health care if they have a mental illness, somatoform disorders being the most powerful risk factor. The results are consistent with the findings among internal medical patients.