This study clarifies the level of involvement for HRQoL in people with cMSS, compared to those with aMSS and those with woMSS. This study found that the following are risk factors for low HRQoL: the female sex, age over 44 years and rural area of residence. On the other hand, high educational level was found to be a protective factor.
The literature indicates that, in the context of a chronic disease, it is necessary to consider the subjective HRQoL assessment based on psychological functioning (mental health) and the degree of physical functioning damage (physical health)(1). Along with this, it is proposed that single subject or population normality or abnormality HRQoL values should be according to a reference group, due to the marked effect of culture on health and disease (1). The present study provides HRQoL scores (in its physical and mental composite scores) in the Chilean population that suffers cMSS as compared to the general population.
In relation to chronic pain, cMSS worldwide prevalence demonstrate wide ranges (12 to 41%) (21), which would be explained by the different definitions for chronic pain, types of studies, data collection methodology and measurement instruments. The present study reports a higher prevalence than the upper limit of the previously reported range. The foregoing could be explained as similar prevalence is presented in studies with the same cut-off points of chronic pain (3 months duration) and similar methodologies of data collection (population surveys type face-to-face interviews) (22). Additionally, the present study results resemble similar outcomes across Latin America; In Colombia, a cross-sectional descriptive population study in urban areas reported a chronic pain prevalence of 33.9% (7) and in Brazil, a cross-sectional population study in São Luís exhibited a 42.3% prevalence (8).
A study conducted in Ireland obtained a 62.6% cMSS prevalence, which is greater than that found in the present study. This could be explained because the population from which the data were obtained, which was a sample drawn from current pain patients (23). Subjects who were interviewed through a national telephone survey generated a low response rate (16.6%) (24).
Another factor that could create disparity in reported chronic pain prevalence centers on the high heterogeneity in chronic pain definitions and the different methodologies used for evaluating population studies worldwide. These disparities make difficult the ability to relate global epidemiological chronic pain findings with consistency in healthcare policy across countries (11, 25).
Musculoskeletal morbidities occur across the life cycle, where their pathophysiology is generally independent of age. Moreover, they share a scarce association with mortality, which could cause delay in a person’s healthcare-seeking behavior. These factors, coupled with Chilean healthcare access limitations, lend to cMSS prevalence (42.6%) being higher than the national prevalence for dyslipidemia (38.5%), hypertension (26.9%), respiratory symptoms (24.5%). %), depressive symptoms (17.2%) and type 2 diabetes (9.4%) (17). This cMSS tendency is furthered by lower HRQoL scores in both mental and physical dimensions.
This is consistent with research assessing HRQoL measured through SF-12, which suggests that quality of life is reduced in chronic pain sufferers, even when cMSS intensity is low (23). A cross-sectional survey study developed in Japan, showed that when using SF-12 to measure HRQoL in cMSS patients and comparing those data with asymptomatic individuals, both physical (PCS 44.23 vs 47.48; p <0.05) and mental (MCS 44.26 vs 51.14, p<0.05) scores demonstrated differences that exceeded the established clinically relevant cut-off points, emphasizing the dramatic effect of chronic pain in the patient's health experience (26).
In a study carried out in Brazil, people with chronic pain presented with significantly lower (P<0.001) health-related quality of life scores (measured through EuroQol), (22). In Ireland, chronic pain patients reported lower physical and mental HRQoL scores compared to the normal population (23). The mental composite scores (MCS) were lower versus physical composite scores, which confirms that the HRQoL should be treated as a multidimensional construct (2).
The multiple logistic regression analysis shows that the cMSS variable is independent of the control variables (sex, age, educational level and residence area) in its ability to explain the presence of "low HRQoL", both in PCS as in MCS. However, this study’s findings show that the female sex and the increase in age are risk factors and that the high educational level is protective factor of presenting "low HRQoL". These considerations should be incorporated into national health program planning, especially in the following groups: women, elderly and people with medium and low educational level.
In women's health care programs, such as "Chile Crece Contigo", MSS management strategies should be identified. A consideration for cMSS could help avoid chronicity of these, and therefore increase the HRQoL in them.
The national program "MAS adultos mayores autovalentes", which seeks to address the functional impairment of older adults and improve their functional independence, should be addressed with MSS screening, since such ailments in its chronic stage could affect the functionality in elderly persons.
In relation to the approach in groups of medium and low educational levels, it is necessary to establish dissemination strategies to health professionals in primary health care, especially in vulnerable sectors. The aim of investigating subjects that, considering their educational level, could be considered more chronic in MSS added to a social context of minimum health priorities in many unsolved cases. This could be due to greater physical labor demand, ignorance of the need for early management and consultation in case of musculoskeletal diseases.
The research results illustrate the evolution of HRQoL results in MSS between the National Health Surveys 2009-2010 and NHS 2016-2017, whose data will soon be available. In Chile, the best approach to MSS management has not been determined (27). Before concluding the best approach, biomedical and biopsychosocial factors must be further considered. The biopsychosocial approach emphasizes the patient's self-management and their HRQoL. This explains the existing training gap that health professionals face within this epidemiological problem. This study’s findings support the need to establish standardized management policies and practices for treating chronic MSS(27).
This study was strengthened by performing the analysis on population data, which allows a generalized application and reflects Chile’s state of health. One study limitation centers on study methodology. Since the study used an analytical cross-sectional approach, the methodology does not imply a cause-effect relationship.