Back pain (BP) includes acute (less than 6 weeks), chronic (pain lasting more than 12 weeks), or neuropathic pain in the upper or lower back. BP is a leading contributor to disability and activity limitation and has been estimated to account for 37% of the global burden of musculoskeletal disorders (MSDs) . In addition, low back pain (LBP) remains the leading cause of years lived with disability (YLDs) among adults, accounting for 64.9 million YLDs . Although BP can be a self-limiting condition, the re-occurrence rate is high (approximately 60%) and individuals are likely to experience another episode within 3–6 months [2, 3]. Limitation of activities because of LBP may result in loss of productive work time, increased medical expenditure, and further entrenchment of low-income individuals in poverty [4, 5].
The most common risk factors for BP include demographic characteristics, personal health habits, psychological factors, occupational exposures, and other chronic comorbidities [4, 6–11]. Prior reviews have established heavy manual work, non-neutral work postures (bending and twisting, repetitive motions, and long working hours) as risk factors for BP among occupational populations [8, 9, 12, 13]. Biological sex and gender are also risk factors; females have a higher prevalence of LBP in the general population than men ([14–17]. A global burden of disease study found that the age-standardized prevalence of LBP is also higher among women than men .
The gendered difference in BP has been attributed to several occupational factors, such as differential exposures to work-related physical and physiological factors, male-oriented tool and workstation designs, and gendered variation in the perception of pain [11, 18–20]. Generally, women tend to be clustered in specific occupations with different pattern of employment and exposures from those of men . However, several occupational studies and reviews have shown that women-dominated jobs may be just as physically taxing as male-dominated jobs [11, 16, 17, 22–24]. Thus, women’s unique occupational exposures may place them at risk for MSDs, including BP .
Additionally, millions of women experience strenuous daily work conditions in low-waged or unpaid domestic labor, often in addition to a formal job. Women’s domestic labor, which involves tasks such as cleaning, cooking, water fetching, manual washing of clothes, and family care duties, may be as physically, emotionally and time demanding as structured paid work [25–29]. In some LMICs, women spend an average of 10 hours per day engaged in strenuous domestic task in awkward postures . Yet, few studies have examined the effects of the physical demands of domestic work (PDDW) on the musculoskeletal health of women. Social norms dictate domestic work as a woman’s duty in many low- and middle-income countries (LMICs). This may discourage spousal and familial involvement in domestic roles even while women increasingly participate in the paid workforce. The double-burden of exposure from paid and unpaid work is particularly problematic among low-income populations where there are limited social services to relieve burdens [28, 31, 32].
Few systematic reviews have assessed gender-specific relationships between PDDW and BP in the general population [33, 34]. Previous meta-analyses of the relationship between non-occupational physical activities (such as sporting, commuting and domestic physical activities) and BP combined results from different types of non-occupational physical activities and did not present stratified results from domestic work demands [33, 35]. Some of these reviews were also limited to studies published in English [33, 36].
Currently, no meta-analysis has assessed the association between PDDW and BP among women. This systematic review aims to fill this gap by examining the contribution of PDDW to the risk of BP among women. We included research studies that both defined domestic work exposures and presented female-specific effect estimates. We also conducted subgroup analysis by country type (high income countries versus LMICs) and definitions of exposure to explore how these issues influence the relationship between PDDW and BP.