Malnutrition is known as a common disorder, which is probably under-recognized. It is defined as a state of nutrition in which a deficiency or excess of energy, protein and other nutrients affects shape, size, composition and function of body and may lead to clinical disease. ¹ In older ages, it may lead to general weakness, exacerbate previous diseases, alter their prognosis or increase their mortality. ²

Malnutrition may occur due to such different causes as dietary deficiencies, chewing or swallowing problems, gastrointestinal or endocrine disorders, loss of taste or smell, decreased appetite, consuming different kinds of drugs, immobility, social isolation, inflammatory diseases, chronic diseases, alcoholism, malignancies and cognitive disorder especially depression. ³,⁴,⁵,⁶,⁷,⁸,⁹,¹⁰,¹¹

Just like malnutrition, depression common in geriatrics ¹² and as a pre-disposing factor for mortality and morbidity in this group. ¹³

Body and mental status have a powerful relationship so lowering of neurotransmitters cause the decrease of mental flexibility and this can lend to important symptom such as: Functional limitation, anorexia and weight loss and malnutrition. ⁸,¹⁴,¹⁵ Malnutrition and psychiatric problem are among prevalent in rural elderly people and depression often has seen in malnourished elderly. ¹⁶,¹⁷,¹⁸,¹⁹ In this study, we therefore, decided to investigate the association of between malnutrition and depression in rural elderly.

This was a cross-sectional study (2011-2012) conducted on 370 elderly living in 36 rural in Isfahan. The older adults were selected by a systematic sampling method. Subjects older than 60 years old entered the study. The data was collected using a questionnaire. The questionnaire consisted of three parts: The first part included socio-demographic characteristic (Age, Sex, level of education, lifestyle, Independent state, Job, type of home) and history of diseases (Hypertension, Diabetic, Osteoporosis, Hyperlipidemia, Arthritis, Cancer, Depression), which were obtained by self-report and Anthropometric dimensions including calf circumference, mid-arm circumference, weight and height were measured. Body mass index (BMI) was calculated by dividing weight (in Kg) by the square of height (in m); the second part included questions to assess depression, which has been validated in Iran, ²⁰ The questionnaire was a tool that can be used to screen the elderly patient at risk of depression and had 15 questions that there were for each question, Answer yes and no, Subjects were classified normal (score 1-4), Mild depression (score 5-9), Severe depression (score 10-15) and the third part consisted of mini nutritional assessment (MNA), which is a standard questionnaire for evaluating nutrition status: ²⁰ Malnourished (score <17), at risk of malnutrition (score 17-23.5) and well-nourished (score >23.5).

The data were analyzed by SPSS ¹⁶ using descriptive statistics, t-test, Chi-square test and logistic regression. P value of < 0.05 was taken to define statistical significance. The study was approved by the ethical research committee of Isfahan University of Medical Sciences and this study performed in rural because some previous researchers found that malnutrition and mental problems (depression) were more common in rural than urban areas in Iran. ²¹

Mean age of the subjects was 70.6 ± 7.3 years ( 60-92 years). Prevalence of depression was 50.3% (female 54 .6%, male 42.3%) that 36.8% had mild depression and 13.5% had severe depression. Mild depression was higher in female than male 65.4% versus 34.6%, respectively and this correlation in severe depression was significant (P < 0.005). Furthermore, there is a significant relationship between depression and job so that unemployed elderly more suffer depression than others (P < 0.002) whereas age level education and life-style had no influence.

According to MNA, 3.8% of subjects suffered from malnutrition, 32.7% were at risk of malnutrition and 63.5% were well-nourished. Malnutrition was not associated with socio-demographic characteristics but it was significantly correlated with depression and BMI Table 1. The risk of malnutrition in patients with severe depression was 15.5 times higher than non-depressed persons (OR: 15.5; 95% CI 2.9-82.5) Table 2.{Table 1}{Table 2}

In the current study, the prevalence of malnutrition and its relationship with influencing factors in elderly were assessed. The prevalence of malnutrition in our study was 3.8%, similar to the results obtained by Eshaghi et al., but this measurement was 12.8% in the study of Afkhami et al. and 7% in the study of Rodriguez et al. which was higher than our study. ²²,²³,²⁴ This difference may be explained that these studies were done in institutionalized older adult and may be rate of malnutrition was higher in this group.

Malnutrition and depression have emerged as important problem among elderly. ¹² In our study, the older adult with depression are prone of malnutrition (16.4%). Some of study identified an independent association between depression and malnutrition. ¹¹,²²,²⁵,²⁶ Well-being is necessary for maintenance of best nutritional status. ²⁷ On the other hand, geriatrics with regular eating program have better psychiatric performance. ²⁸ Thompson et al. found a sign of depression in elderly is change in eating behavior ²⁹,³⁰ and treatment of depression caused a decreased of weight loss in elderly. ³¹ Probably depression influences the appetite, food in-take and reduced energy in-take and this can lead to weight loss and increase the risk of malnutrition. Prevalence of depression in our study was 50.3% (female 54.6%, male 42.3%) and female had more depression than male this gender difference may to some extend be explained by an under-reporting of depressive symptoms by male individuals. There were significant relationship between depression and job so that unemployed elderly had more suffer depression than employ people. Mokhber et al. found depression in geriatric with personal income was lower. ²¹ In present study, all of the older adult were low schooling and most of them low socio-economic (unemployed) level, probably these induce to depression and malnutrition.

In the present study, malnutrition significantly was higher in elderly with normal BMI. Some other studies have described the relationship between BMI and malnutrition. ²³,³² It was reported that with advancing age, lean body mass decreases and the amount of body fat generally increases until age 70 after which it decreases again. ³³,³⁴ Thus, it seems likely that the relationship between body fatness and BMI changes with advancing age.

In our study, the effect of age on malnutrition was not significant. This result was against other studies in which age affected the nutritional status in elderly. ⁶,²⁶,³⁵,³⁶ Generally in this study, it was demonstrated that the prevalence of malnutrition in females was not higher than males. Rodriguez et al. reported similar results; however, in some other studies women have been suffered from malnutrition. ²⁶,³⁵,³⁷ Difference between our result and other study maybe return to our small sample size.

We did not found significant correlation between the life-style and malnutrition in elderly. Elderly who live alone are at higher risk of malnutrition than others. ²⁴ This discrepancy could explain by social, cultural or economic factors in our population that most of the old subjects are living with our children.

In this study, 1.6% of elderly was functionally dependent and was not different from independent ones regarding the state of nutrition. Morely et al. and Paytte reported that functional disability in elderly is associated with inadequate food in-take and weight loss. ³⁸,³⁹ Saka et al. compared nutritional state of their functionally depended and independent subjects and found a poor nutritional state with lower daily calorie in-take in dependent subjects. ⁴⁰ Malnutrition is more frequent in elderly who are functionally dependent .

A potential limitation of this data is that the population of elderly people in our study was limited to many rural community in the central city of the country and may not be generalized to all other elderly both living conditions and health-care organization different with our health-care organization.

According to our research, there is a lot of evidence that malnutrition and depression a common among elderly and may lead to deleterious effects on health and well-being. Hence, detecting alterations in primary care is important in order to improve quality of life and reduce complications. Since malnutrition is multi-factorial in origin and mostly several other problems are present concurrently, it is important to mention that nutritional interventions should be implemented only as a part of a complete strategy. Inter-disciplinary efforts directed toward increasing nutrient intake and removing pre-disposing causes of malnutrition should be encouraged.

Further investigations are necessary to show the need for a team work consisting of gerontologists, psychiatrics, anthropologists, clinicians, nutritionists, and other specialists involved in the care of elderly to generate guidelines in order to prevent and/or treat the elderly′s malnutrition or decrease its risk.

We thank the staff and family of the elderly for their assistance in this study. This study was supported by the Vice-Chancellor for research, Isfahan University of Medical Sciences N.290038.