This study revealed that the HGS level decreased significantly with age and was distinctly increased among males. A similar finding was also seen in contemporary and modern eras across the continent [15-17]. Furthermore, this finding regarding sex can be explained by the fact that females have less muscle mass than males  as a result of a low level of testosterone and differences in the amount of insulin-like growth factor-1 (IGF-1) and growth hormone (GH) . Testosterone increases fast fibres with high glycolytic enzyme activity called type II fibres , which are present in high proportions in males. Moreover, high bone mineral density in males also contributed to the higher HGS among males than among females .
In the multivariate analysis, elderly males were found to have more factors associated with HGS than females. The proportion of elderly males who were employed and retired from a job, smoked and consumed alcohol was greater than that of females. Elderly males who were employed and retired from a job had significantly higher HGS than those who never had a job. Elderly individuals who were working or employed may participate in more active physical movement. Physical activity directly stimulates skeletal muscle and subsequently leads to improved muscle mass and higher HGS . Coincidently, this study found that a lower frequency of physical activity was associated with lower HGS.
In terms of household income, although household income was not significantly associated with HGS in sex subgroups, the overall elderly sample with no income had lower HGS. This can be related to a previous study, as those in this group were physically inactive , which reflects that education and resources are ultimately important in preserving HGS in elderly individuals as an outcome of a healthy lifestyle.
Interestingly, this study found that alcohol consumers had higher HGS than nonconsumers. Although excessive drinking has been shown to be associated with sarcopenia , light-to-moderate alcohol intake has also been shown to have a protective effect against muscle mass loss . Similar findings as those observed in this study were observed in a European and Koran study . Further research is needed to ascertain the positive effects of alcohol consumption on HGS, in view of many other factors that can manipulate the result, such as the amount of alcohol, which was not measured in the study. Likewise, smoking was also found to be associated with higher HGS in this study. Perhaps this can be linked to other factors, such as occupation and physical activity of the smokers since most smokers comprised those with low socioeconomic status . Although some studies have shown that smoking has negative effects on HGS [28, 29], several other studies have shown mixed results on the effect of smoking [26, 30]. Additionally, a study noted low HGS among smokers with COPD as a predictor of future acute respiratory events [31, 32]. Hence, further research is needed to understand the effect of smoking on HGS.
In terms of HGS and comorbidities, this study revealed that lower HGS was significantly associated with underweight, while obesity was associated with higher HGS. This finding was consistent with a previous study [33-36]. BMI is related to fat and muscle mass; hence, low BMI is associated with low fat and muscle mass . The ageing process, as well as low muscle mass, contribute to low muscle strength . Additionally, poor nutritional intake, as observed in undernourished individuals, could also affect muscle mass [36, 37], but this was not measured in this study. Moreover, few studies have found contradictory results regarding the relationship between central obesity and HGS [39, 40]. Careful interpretation of the result is needed since the total weight used in the calculation of BMI, as a surrogate indicator of adiposity, includes fat mass and fat-free mass . On the other hand, the presence of diabetes was associated with low HGS. Similar findings were noted in a previous study [41, 42], which can be attributed to diabetic neuropathy [43, 44]. Moreover, the duration of diabetes has been shown to be associated with lower HGS [45, 46], which supports the theory of neuropathy since neuropathy is one of the complications of chronic poorly controlled blood sugar levels. In addition, the insulin resistance state within skeletal muscle occurs as a result of greater intramuscular adipose tissue and muscle atrophy , thus damaging skeletal muscle . In view of the apparent association between HGS and diabetes, HGS has been proposed to be used as a diabetes screening tool among apparently healthy adults .
We found that better self-rated health status in elderly males was associated with higher HGS. This is in agreement with a study conducted in Indonesia  and could be explained by the fact that better self-rated health indicated no or less disease and that many diseases are associated with poorer self-rated health . In this study, we excluded participants who had poor cognitive function. In this study, difficulty in remembering or concentrating may reflect early cognitive impairment, and we found that normal memory and concentration were associated with higher HGS. In a review performed by Fritz et al. , poorer cognitive function was associated with lower HGS. The reason for cognitive decline and lower HGS may be based on the understanding that motor skill learning and motor output are dependent on the activity of the frontal and parietal brain regions [52, 53]. We also found that the presence of depression was not significantly associated with HGS, and a significant but weak correlation was found between GDS and GHS. However, many studies have revealed a significant association between depression and HGS [33, 54, 55].
Given that most of the variables were self-reported and no confirmation of the data was available, the results must be interpreted carefully. However, we measured depression symptoms through the validated GDS. Nevertheless, the study is a population-based study with a large sample size. Although the respondents were chosen at random, the study sample managed to cover a good proportion of the elderly population and was similar to the demographics of the elderly population in Malaysia.
In conclusion, there are slight differences between male and female elderly individuals in the factors that influence HGS. Overall, factors such as sociodemographic factors (age, sex and household income), lifestyle factors (smoking, alcohol intake and moderate exertion of physical activity) and comorbidities (BMI and diabetes) were associated with HGS. By identifying these factors, good HGS can be preserved, which can subsequently prevent disability in elderly individuals, hence ensuring a good quality of life. Therefore, the routine use of hand grip measurement is strongly recommended in clinical practice for identifying elderly individuals at risk of poor health status.