The findings of this study revealed that at least seven out of ten elders participating in this study had a moderate level of QOL. Moreover, elderly women, elders with chronic diseases (sleep disturbance, osteoporosis), and those who were not the source of their family income had a lower level of QOL. Moreover, facing violence was inversely correlated with both CCQOL and MQOL in the elders and sexual problems. No supplementary insurance coverage decreased the elders’ MQOL. Among chronic diseases, sleep disturbance had the most inverse relationship with QOL and CCQOL, while sexual problems had the strongest relationship with MQOL. Furthermore, physical functioning and perceived personality had the strongest correlation with CCQOL and MQOL, respectively.
Population aging is one of the most challenging public health issues in today's world (
16); as a result, the prevalence of chronic diseases and the need to care for elderly adults have increased (
17). On the other hand, achieving a higher level of QOL in the elderly has been more concerned by policymakers compared to solely raising their life expectancy (
18). However, unlike developed countries, developing countries are not prepared enough to manage the health, social, and economic consequences of aging (
4).
A meta-analysis study in Iran showed that elderly men had higher levels of QOL than older women (
8). This finding was in line with the findings of the present study. Another review study in Iran revealed that 50% of elderlies had a moderate level of QOL (
10).; the reported value was below the value reported for the moderate level of QOL in the present study (70%).
Zeitlhofer et al. in Austria reported a significant relationship between sleep quality and the total score of QOL. They suggested that poor sleep quality could be used as a screening method in examining patients' QOL (
19), which is in line with our findings. The relationship between quality of sleep and QOL was also documented in another study (
20).
Similar to our findings, Lips, and van Schoor (
21) and Madureira et al. (
22) found a relationship between osteoporosis and lower levels of QOL in the elders. Lee and Shinkai revealed that gender was not correlated with QOL (
23), which is in contrast to our findings. Lemos et al. also concluded that QOL was lower in elderly females than in elderly males (
24). In contrast to some other studies (
25,
26), we found no association between the low level of income and QOL; however, there was a positive association between being the source of family income and QOL. This finding has not been reported in other studies. We also showed that the place of birth (urban vs. rural) of the elders and their spouses had no relationship with their QOL. This finding is inconsistent with those from another study conducted in Spain (
27). In recent years, scientists have been more concerned with different aspects of sexuality as the determinants of QOL in the elders. Flynn and Gow concluded that sexual function is a significant predictor of QOL in elderly adults (
28). We also concluded that sexual function was positively correlated with MQOL in the elders. Moreover, the prevalence of depression has increased in many countries, including the Middle East, over the past two decades (
29). Similar to our study, Canuto et al. indicated that the incidence of depression and anxiety disorders had a negative relationship with QOL in the elders, especially in women (
30). In another study, violence toward elders was associated with their lower levels of QOL, as we reported in this study (
31). Brovold et al. showed that physical function had a significant relationship with aging, implying that it is important to encourage elders to be physically active and thereby promote their QOL (
32). Similarly, physical function was the strongest predictor of CCQOL among the other components. Our study had some limitations and strengths. We could not assess the QOL of those elders who were not under the coverage of health centers. However, the participants of this study consisted of only about 5% of all elders in Shiraz city. Moreover, there are limited nursing homes in this city. Another point is that to detect causal relationships between QOL and other factors, further longitudinal studies are recommended. On the other hand, as one of the strengths of this study, the present research was among scarce studies assessing MQOL and its relationship with QOL in the elders. Furthermore, we also measured the correlation between different socioeconomic, demographic, anthropometric, and medical backgrounds with QOL, CCQOL, and MQOL. Further, the correlations between the components of CCQOL and MQOL with their relevant scores were also investigated.