Prevalence of Organic Mental Disorders in a General Hospital in Izhevsk, Russia

Background and Objectives: At the moment, studies of organic mental disorders (OMD) in in-patients of therapeutic units in Udmurtia are limited. The paper’s objective was to study the prevalence and risk factors of OMD in medical patients in one of the municipal hospitals of Izhevsk. Methods: The subjects (323 patients aged from 18 to 59 years) were selected using the method of continuous sampling. All subjects were asked to answer the questions from the Russian version of the Brief International Neuropsychiatric Questionnaire (MINI 5.0.0.). Results: The prevalence of OMD was 55.1%. OMD were more common in older patients (50-59 years) and in patients with chronic somatic diseases. 36.5% of patients with OMD were diagnosed with pre-dementia. The comorbidity of OMD with other mental disorders was statistically significant for depression and anxiety disorders. Conclusion: Knowledge of OMD risk factors can contribute to early detection and adequate treatment of OMD in patients of general hospitals.

The subjects were selected using the method of continuous sampling. The group included every patient aged 18 to 59 referred to the hospital unit number 1. The average length of hospitalization per patient was 18.3 days. A total of 352 patients were selected for the study. 29 of them (11 men and 18 women) were not included in the study for various reasons (refusal, severe somatic condition, etc.). Consequently, the study sample consisted of 323 patients, including 147 (45.5%) men and 176 (54.5%) women. Ethnic background of the study population: 214 (66.3%) Russians, 77 (23.8) Udmurts and 32 (9.9%) other. All participants were divided into the following age groups: 18-39 years-37%, 40-49 years-31% and 50-59 years-32%. 71.5% of the study population were hospitalized due to exacerbation of a chronic somatic disease and 28.5% -due to an acute somatic disease.
All subjects were asked to answer the questions from the Russian version of the Brief International Neuropsychiatric Questionnaire (MINI 5.0.0.) [15]. Additionally, the survey used the diagnostic criteria of ICD-10 for organic mental disorders and the criteria for tobacco addiction. MINI is a standardized diagnostic interview for major mental disorders according to DSM-IV and ICD-10. The reliability and validity of MINI correspond to SCID-P and CIDI, but an important advantage of MINI is that interviewing requires less time.  The manuscript has been assessed by the Ethics Committee (Institutional Board Review) in the Izhevsk State Medical Academy.  The OMD prevalence in the sample was 55.1% (178 cases).

A. Table 1 Shows a Breakdown of Diagnoses in the Study Population:
The average age of the respondents with OMD was 46.6 years (Std. Dev. = 10.2). The average OMD duration was 6.4 years, with the minimum less than one year and the maximum of 45 years (Std. Dev. = 6.4). (Table 3):

Discussion and Conclusion
According to numerous Russian and foreign studies, it has been proven that there are strong structural links between comorbid organic mental disorders and somatic disorders [1] -this fact was confirmed in our study. More than a half of the sample in this study had OMD (55.1%). The most common OMD diagnosis was organic asthenic disorder (51.1% of all OMD). 36.5% of the respondents with OMD had decreased cognitive functions -pre-dementia, and 2.8% were diagnosed with dementia. It is noteworthy that a lot of respondents in the sample (most of whom were at their working age) were diagnosed with pre-dementia or, as it is called in some sources, mild cognitive impairment (MCI) [17]. According to different data, the prevalence of the MCI syndrome among elderly and senile patients (65 years and older) varies from 7% to 38%. It is known there is an increased risk of the MCI syndrome transition to dementia within the next 3 to 5 years [18]. According to a group of researchers from New York University, 42% of people initially diagnosed with the MCI syndrome were diagnosed with dementia in 5 years with only 7% of the patients being in the age-norm group The researchers emphasize it is not a somatic pathology but its severity and duration that play a role in the development of OMD.
Apparently this is why OMD were statistically more often diagnosed in patients with chronic rather than acute somatic diseases (70.1% vs 17.4%). Moreover, 100% of the respondents with diseases of the circulatory or musculoskeletal systems were diagnosed with OMD. High occurrence of OMD was observed among patients with diseases of the digestive and respiratory systems -90.6% and 77.8% respectively.
There was no correlation between OMD and such sociodemographic factors as gender, ethnicity, marital status, education or social status. There was a reliable correlation between OMD and the age of the patients, probably because of the greater occurrence of chronic somatic diseases and accumulation of cerebrovascular diseases in elderly patients [4]. Thus, the epidemiological indicators of OMD in the general hospital were extremely high, especially among patients with chronic diseases. One third of patients with OMD were diagnosed with mild cognitive impairment, and according to medical sources, there is a high risk that this condition may transform into dementia in the next few years.
Such results may indicate insufficient diagnostics and lack of OMD treatment. The reasons for the under-diagnosis may be insufficient psychiatric care in hospitals and lack of awareness among therapists of the OMD clinical picture. Awareness of epidemiology and risk factors can contribute to early detection and treatment of OMD. Identification and appropriate treatment of OMD is an extremely important task due to the unfavorable prognosis.