This is the first study to evaluate the prevalence of these two diseases by gender, covering all regions in the Turkish population. In the Turkish population sample, the prevalence of NP alone in 1 year in 2019 was 6.27%, LBP alone was 16.11%, and both LBP and NP were 17.11%. A total of 39.49% of the sample was exposed to LBP and/or neck pain. The 1-year prevalence of NP was 34% [16] in the British population, the 1-year prevalence of LBP was 42.4% [17] in Sweden, and the 1-year prevalence of LBP in Africa was 33% in adolescents and 50% in adults [18].
The parameters that derive the maximum likelihood value of the random-effects ordinal probit model for pooled and sex differences are presented in Table 2. However, our next discussion has focused on marginal effects, as it is more appropriate to discuss the prevalence probability of each disease burden rather than discussing parameters in the maximum likelihood function. In the random-effects ordered probit model, the marginal effects showing the change in the prevalence rates of the ordered dependent variables concerning a one-unit change in the independent variables are presented in Table 3.
Table 3
Marginal effects of covariates on the different prevalences of male, female, and pooled samples
Variables | Pooled sample | Male Sample | Female Sample |
Pain free | Single pain(NP or LBP) | Dual pain (NP&LBP) | Pain free | Single pain (NP or LBP) | Dual pain (NP&LBP) | Pain free | Single pain (NP or LBP) | Dual pain (NP&LBP) |
Coeff.*100 | p value | Coeff.*100 | p value | Coeff.*100 | p value | Coeff.*100 | p value | Coeff.*100 | p value | Coeff.*100 | p value | Coeff.*100 | p value | Coeff.*100 | p value | Coeff.*100 | p value |
Individual characteristics |
Age 30–44 | -11.755*** | 0.000 | 4.426*** | 0.000 | 7.329*** | 0.000 | -5.204** | 0.014 | 2.804** | 0.012 | 2.400** | 0.017 | -14.512*** | 0.000 | 3.663*** | 0.000 | 10.849*** | 0.000 |
Age 45–64 | -18.487** | 0.000 | 6.715*** | 0.000 | 11.772*** | 0.000 | -11.647*** | 0.000 | 6.130*** | 0.000 | 5.518*** | 0.000 | -23.978*** | 0.000 | 5.522*** | 0.000 | 18.457*** | 0.000 |
Age > 64 | -21.215*** | 0.000 | 6.518*** | 0.000 | 14.696*** | 0.000 | -14.789*** | 0.000 | 7.243*** | 0.000 | 7.546*** | 0.000 | -28.538*** | 0.000 | 3.847*** | 0.000 | 24.691*** | 0.000 |
Unmarried | 11.696*** | 0.000 | -5.252*** | 0.000 | -6.444*** | 0.000 | 6.540** | 0.027 | -3.727** | 0.032 | -2.813** | 0.021 | 10.645*** | 0.000 | -3.637*** | 0.000 | -7.009*** | 0.000 |
Married | 4.251*** | 0.003 | -1.677*** | 0.002 | -2.574*** | 0.003 | 0.413 | 0.881 | -0.227 | 0.881 | -0.186 | 0.882 | -0.070 | 0.967 | 0.021 | 0.967 | 0.050 | 0.967 |
Elementary school | 6.947*** | 0.000 | -2.905*** | 0.000 | -4.042*** | 0.000 | 7.454*** | 0.001 | -4.191*** | 0.001 | -3.263*** | 0.001 | 3.877** | 0.011 | -1.164** | 0.013 | -2.713*** | 0.010 |
Secondary school | 9.922*** | 0.000 | -4.435*** | 0.000 | -5.487*** | 0.000 | 7.709*** | 0.001 | -4.449*** | 0.002 | -3.259*** | 0.001 | 7.629*** | 0.000 | -2.523*** | 0.001 | -5.106*** | 0.000 |
High school | 11.247*** | 0.000 | -4.994*** | 0.000 | -6.253*** | 0.000 | 9.052*** | 0.000 | -5.205*** | 0.000 | -3.847*** | 0.000 | 10.188*** | 0.000 | -3.415*** | 0.000 | -6.772*** | 0.000 |
College | 11.942*** | 0.000 | -5.344*** | 0.000 | -6.598*** | 0.000 | 10.205*** | 0.000 | -5.917*** | 0.000 | -4.288*** | 0.000 | 11.365*** | 0.000 | -3.868*** | 0.000 | -7.498*** | 0.000 |
Working | 8.219*** | 0.585 | -3.409*** | 0.584 | -4.810*** | 0.000 | 12.190*** | 0.000 | -6.503*** | 0.000 | -5.687*** | 0.001 | -2.683* | 0.063 | 0.758* | 0.054 | 1.925* | 0.066 |
Job seeking | 9.634*** | 0.289 | -4.338*** | 0.300 | -5.296*** | 0.000 | 12.308*** | 0.000 | -7.342*** | 0.000 | -4.966*** | 0.000 | 1.658 | 0.563 | -0.501 | 0.575 | -1.157 | 0.558 |
Retired | 9.825*** | 0.328 | -4.373*** | 0.334 | -5.452*** | 0.000 | 10.246*** | 0.001 | -5.908*** | 0.001 | -4.338*** | 0.000 | -2.909 | 0.166 | 0.802 | 0.140 | 2.107 | 0.176 |
Overweight | -4.242*** | 0.000 | 1.693*** | 0.000 | 2.549*** | 0.000 | -3.933*** | 0.001 | 2.151*** | 0.001 | 1.782*** | 0.001 | -6.666*** | 0.000 | 1.840*** | 0.000 | 4.826*** | 0.000 |
Obese | -7.784*** | 0.000 | 2.914*** | 0.000 | 4.871*** | 0.000 | -6.281*** | 0.000 | 3.305*** | 0.000 | 2.975*** | 0.000 | -9.586*** | 0.000 | 2.395*** | 0.000 | 7.191*** | 0.000 |
Over obese | -11.374*** | 0.000 | 3.903*** | 0.000 | 7.471*** | 0.000 | -14.320*** | 0.000 | 6.794*** | 0.000 | 7.526*** | 0.000 | -10.182*** | 0.000 | 2.362*** | 0.000 | 7.820*** | 0.000 |
General health insurance | -2.078 | 0.153 | 0.865 | 0.163 | 1.213 | 0.146 | 0.247 | 0.901 | -0.136 | 0.901 | -0.111 | 0.901 | -3.787* | 0.065 | 1.190* | 0.084 | 2.597* | 0.057 |
Private health insurance | 0.981 | 0.647 | -0.404 | 0.651 | -0.578 | 0.643 | 4.773* | 0.069 | -2.739* | 0.081 | -2.034* | 0.055 | -2.688 | 0.357 | 0.741 | 0.326 | 1.947 | 0.368 |
Walking | 4.473*** | 0.000 | -1.894*** | 0.002 | -2.580*** | 0.001 | 3.138** | 0.012 | -1.755** | 0.014 | -1.383** | 0.011 | 3.601** | 0.028 | -1.120** | 0.038 | -2.481** | 0.024 |
Sports time | 2.577* | 0.097 | -1.080 | 0.108 | -1.498* | 0.090 | 3.426* | 0.056 | -1.936* | 0.063 | -1.490** | 0.048 | -0.465 | 0.853 | 0.135 | 0.852 | 0.330 | 0.854 |
Resting | -2.944*** | 0.001 | 1.180** | 0.000 | 1.764*** | 0.000 | -1.507 | 0.183 | 0.826 | 0.182 | 0.681 | 0.186 | -3.182*** | 0.005 | 0.911*** | 0.004 | 2.271*** | 0.006 |
Heavy physical job | -1.041 | 0.610 | 0.417 | 0.604 | 0.624 | 0.613 | -2.572 | 0.222 | 0.014 | 0.211 | 1.187 | 0.234 | - | - | - | - | - | - |
Tobacco | 1.868** | 0.022 | -0.759** | 0.022 | -1.109** | 0.022 | -1.040 | 0.374 | 0.575 | 0.376 | 0.465 | 0.371 | -3.950*** | 0.001 | 1.109*** | 0.001 | 2.841*** | 0.001 |
Alcohol | 0.843 | 0.616 | -0.346 | 0.619 | -0.497 | 0.613 | -1.563 | 0.412 | 0.849 | 0.406 | 0.714 | 0.420 | -1.605 | 0.621 | 0.453 | 0.608 | 1.152 | 0.626 |
Fruit consumption | 7.347*** | 0.000 | -2.713*** | 0.000 | -4.634*** | 0.000 | 4.652** | 0.016 | -2.464** | 0.012 | -2.188** | 0.021 | 8.200*** | 0.000 | -2.017*** | 0.000 | -6.183*** | 0.000 |
Vegetable consumption | -1.359 | 0.504 | 0.562 | 0.511 | 0.797 | 0.499 | -1.150 | 0.655 | 0.640 | 0.659 | 0.511 | 0.651 | 0.371 | 0.903 | -0.108 | 0.903 | -0.263 | 0.904 |
Juices (%100) | 1.406 | 0.123 | -0.577 | 0.127 | -0.829 | 0.120 | 1.401 | 0.252 | -0.777 | 0.255 | -0.625 | 0.248 | 1.523 | 0.228 | -0.454 | 0.237 | -1.070 | 0.225 |
Carbonated drinks | 2.921*** | 0.001 | -1.201*** | 0.001 | -1.720*** | 0.001 | 1.338 | 0.245 | -0.738 | 0.246 | -0.600 | 0.243 | 2.621** | 0.027 | -0.785** | 0.031 | -1.836** | 0.025 |
Comorbidity | | | | | | | | | | | | | | | | | | |
Depression | -23.633*** | 0.000 | 6.598*** | 0.000 | 17.035*** | 0.000 | -22.132*** | 0.000 | 9.633*** | 0.000 | 12.500*** | 0.000 | -21.817*** | 0.000 | 3.733*** | 0.000 | 18.083*** | 0.000 |
Family characteristics |
Income 3400–6900 | -0.916 | 0.342 | 0.371 | 0.340 | 0.0546 | 0.343 | -0.159 | 0.901 | 0.088 | 0.901 | 0.072 | 0.901 | 0.411 | 0.743 | -0.121 | 0.744 | -0.291 | 0.743 |
Income > 6900 | 0.013 | 0.999 | -0.054 | 0.999 | -0.079 | 0.999 | 0.001 | 0.955 | -0.055 | 0.956 | -0.045 | 0.955 | 4.357** | 0.017 | -1.362** | 0.024 | -2.995** | 0.014 |
Single person family | 1.059 | 0.545 | -0.436 | 0.550 | -0.624 | 0.542 | 1.754 | 0.517 | -0.980 | 0.523 | -0.774 | 0.509 | -0.294 | 0.896 | 0.086 | 0.895 | 0.209 | 0.896 |
Childless Couple | 0.294 | 0.808 | -0.120 | 0.809 | -0.174 | 0.808 | 2.366 | 0.136 | -0.1321 | 0.142 | -1.045 | 0.129 | -0.974 | 0.537 | 0.281 | 0.531 | 0.693 | 0.540 |
# of kids aged 0–6 | 3.701*** | 0.000 | -1.503*** | 0.000 | -2.199*** | 0.000 | -0.001 | -0.992 | 0.001 | -0.992 | 0.001 | -0.992 | 4.321*** | 0.000 | -1.264*** | 0.000 | -3.057*** | 0.000 |
# kids aged 7–14 | 0.661 | 0.282 | -0.269 | 0.282 | -0.393 | 0.282 | -0.433 | 0.601 | 0.239 | 0.601 | 0.195 | 0.601 | 0.843 | 0.293 | -0.247 | 0.293 | -0.596 | 0.293 |
# of adults | 0.691 | 0.149 | -0.281 | 0.150 | -0.410 | 0.149 | 1.213* | 0.058 | -0.668* | 0.058 | -0.545* | 0.057 | -0.069 | 0.908 | 0.020 | 0.908 | 0.049 | 0.908 |
Istanbul | -4.580** | 0.018 | 1.765** | 0.012 | 2.816** | 0.022 | -9.221*** | 0.001 | 4.718*** | 0.000 | 4.503*** | 0.001 | -0.276 | 0.911 | 0.080 | 0.910 | 0.196 | 0.911 |
Western Marmara | 0.342 | 0.865 | 0.138 | 0.864 | 0.203 | 0.865 | -1.571 | 0.551 | 0.854 | 0.546 | 0.717 | 0.557 | 1.119 | 0.666 | -0.334 | 0.672 | -0.785 | 0.663 |
Eastern Marmara | 3.505 | 0.138 | -1.489 | 0.155 | -2.017 | 0.125 | -3.968 | 0.232 | 2.106 | 0.214 | 1.862 | 0.251 | 10.888*** | 0.001 | -3.870*** | 0.003 | -7.018*** | 0.000 |
Aegean | -7.305*** | 0.002 | 2.674*** | 0.001 | 4.631*** | 0.004 | -12.100*** | 0.000 | 5.919*** | 0.000 | 6.181*** | 0.002 | -3.608 | 0.227 | 0.977 | 0.188 | 2.631 | 0.241 |
Mediterranean | -0.025 | 0.990 | 0.010 | 0.990 | 0.015 | 0.990 | -4.750* | 0.084 | 2.516* | 0.072 | 2.234* | 0.099 | 4.172 | 0.111 | -1.312 | 0.135 | -2.860* | 0.100 |
Western Anatolia | -4.565 | 0.135 | 1.733 | 0.107 | 2.832 | 0.152 | -10.066** | 0.024 | 4.997** | 0.011 | 5.069** | 0.042 | 1.178 | 0.757 | -0.354 | 0.762 | -0.825 | 0.754 |
Central Anatolia | 0.199 | 0.916 | -0.081 | 0.916 | -0.118 | 0.916 | -3.892 | 0.127 | 2.083 | 0.116 | 1.809 | 0.140 | 4.858** | 0.047 | -1.533* | 0.064 | -3.325** | 0.040 |
Western Black Sea | -0.247 | 0.912 | 0.100 | 0.911 | 0.147 | 0.912 | -3.442 | 0.294 | 1.837 | 0.278 | 1.605 | 0.311 | 1.833 | 0.516 | -0.555 | 0.530 | -1.278 | 0.510 |
Eastern Black Sea | -4.687** | 0.011 | 1.825** | 0.008 | 2.861** | 0.013 | -8.764*** | 0.000 | 4.580*** | 0.000 | 4.183*** | 0.001 | -0.407 | 0.864 | 0.118 | 0.864 | 0.288 | 0.865 |
Southeastern Anatolia | -2.934 | 0.253 | 1.144 | 0.233 | 1.791 | 0.266 | -2.905 | 0.400 | 1.557 | 0.387 | 1.348 | 0.415 | -3.444 | 0.307 | 0.934 | 0.267 | 2.510 | 0.322 |
Note: ***, **, and * show statistical significance at the %1, %5, and % 10 levels, respectively, while Prob. stands for probability value |
In the present study, the prevalence of single and dual disease increased as the age of individuals of both sexes increased. For example, when compared to individuals aged under 30, 30–44, 45–64, and 65 and over male individuals, the single disease burden increased by 2.80%, 6.13%, and 7.24%, respectively, while the double disease burden increased significantly by 2.4%, 5.52%, and 7.55%, respectively. However, although the prevalence of single disease burden in females was the same as that in males (3.66%, 5.52%, and 3.85%, respectively), the prevalence of dual diseases has increased markedly (10.85%, 18.46%, and 24.69%, respectively) (for all comparisons P < 0.05). In this context, female individuals aged 65 and over have a 3.27 times higher risk of contracting the dual disease than males, with a very differential potential. The findings are consistent with the literature. In a study investigating the global prevalence of LBP, LBP was found more often in elderly individuals and women [19].
Compared with individuals who were married, the single and dual disease prevalence of being unmarried (never married, widowed, or divorced) was significantly reduced in both men (3.73% and 2.81%, respectively) and women (3.64% and 7.01%, respectively). (P < 0.05 for all comparisons). The incidence of the dual disease is 2.49 times lower in unmarried women than in unmarried men. Similar findings have been reported in the literature, with unmarried men and women (never married, widowed, or divorced) having a lower prevalence of LBP than married men and women [12–22]. In another study, the risk of NP in singles was 76% less than that in married people [23].
As the education level of individuals increases, the prevalence of single and dual illiterate people and/or individuals who do not have any diploma from primary school, secondary school, high school, and undergraduate male individuals, single disease burden decreases significantly by 4.19%, 4.45%, 5.21%, and 5.92%, and double disease burden decreases significantly by 3.26%, 3.26%, 4.29%, and 5.69%, respectively. In the same comparison, the prevalence of carrying dual disease further decreased (2.71%, 5.11%, 6.77%, and 7.50%, respectively) when compared with the prevalence of single disease burden in women (1.16%, 2.52%, 3.42%, and 3.87%, respectively) (P < 0.05 for all comparisons). Especially as the education level of women increases, the prevalence of single and double disease decreases significantly. Graduate women are almost three times less likely to experience single and dual disease than women with primary school degrees. In particular, women at the undergraduate level are approximately 1.76 times less likely to have the dual disease than men. One study [24] and three systematic reviews reported that LBP is less affected in individuals with higher education than in individuals with secondary or lower education [25]. Similar to study findings, a study evaluating NP and LBP also found that subjects with lower education levels were more likely to suffer from NP and LBP [19].
When the referred employment category (disabled people, homemakers, cleaners, and those in compulsory military service) and employees were compared, a significant negative relationship was found between the likelihood of working men having a single illness (6.50%) and double illness (5.69%), and a positive relationship was found between the active work of women and their probability of having a single (0.76%) and double (1.93%) illness. Working women are 3.94 times more likely to have a dual illness than men. Such an outcome may be due to the sum of workloads inside and outside the home. The findings are consistent with the literature results, in which acute and chronic diseases are more common in working women than in non-working women [26]. For the men seeking a job, the odds of catching a single and dual illness are 7.34% and 4.97%, respectively, and for men who receive a pension are 5.91% and 4.34%, respectively, less than those who do not (P < 0.05 for all comparisons).
As the weight of individuals increases, the prevalence of single and dual disease increases significantly in both men and women. Compared with normal-weight individuals, in overweight, obese, and extremely obese male individuals, the single disease burden increased by 2.15%, 3.31%, and 6.79% points, respectively, while the double disease burden increased significantly by 1.78%, 2.96%, and 7.53%, respectively. However, the prevalence of single disease burden in female individuals was lower than that in males (1.84%, 2.40%, and 2.36%, respectively). In comparison, the prevalence of carrying dual disease increased significantly (4.83%, 7.19%, and 7.82%, respectively) (for all comparisons, P < 0.05). The prevalence of dual disease was 7.75% in extremely obese men compared to normal-weight men and 7.82% in extremely obese women compared to normal-weight women. Excessive obesity increases the risk of carrying dual diseases at approximately the same rate in men and women. The relationship between obesity and LBP is well known, but it should be kept in mind that it also increases the risk of NP. The consensus supported by studies [27] and systematic reviews is that obesity (BMI > 30 kg/m2) is associated with musculoskeletal diseases, including chronic NP [20] and LBP [28], and is directly related to chronic spinal pain (CSP) [21].
Women with general health insurance (GSS) were 1.19% and 2.60% more likely to have a single and double disease, respectively, than those who did not. On the other hand, the prevalence of single and dual diseases in males with private health insurance (PHI) was significantly lower by 2.74% and 2.03%, respectively. People with PHI in Turkey have higher socioeconomic and educational levels. These people can go to private health institutions without paying or paying a low fee and access health services more efficiently. This result is consistent with the literature, showing individuals with lower economic status had a higher prevalence of chronic LBP [29] and CSP [21] than those with higher economic status.
Compared with those who did not walk for more than one hour a day, a negative association was obtained between individuals walking for more than one hour a day and their probability of developing back and/or neck disease. Men and women who walked for more than an hour a day had a 1.75% and 1.12% lower risk of developing a single illness, respectively. However, male and female individuals have a 1.38% and 2.48% lower risk of contracting a dual disease, respectively. On the other hand, as the time (minutes) devoted to sports by male individuals per week increases, the prevalence of single and dual diseases significantly mitigates by 1.94% and 1.49%, respectively (P < 0.05 for all comparisons). The burden of carrying a double disease in women walking for more than 1 hour is approximately twice as low as for a single disease. Again, women who walk for more than an hour a day are 1.79 times less likely to contract the dual disease than men. Considering a large number of studies investigating the relationship between LBP and walking [30] and exercise [31], walking and exercise have a neutral or beneficial effect on the risk of LBP. The coexistence of NP and LBP has been reported to be associated with not performing physical exercise and being obese [19].
The study found that the probability of catching a single and double disease in men who consume tobacco was 0.57% and 0.47% points, respectively, and 1.11% and 2.84% points in women compared with nonsmokers (P < 0.05 for all comparisons). The risk of developing the dual disease among female smokers was 6 times higher than that among male smokers. The findings are compatible with the literature. In studies investigating risk factors in people with LBP [32, 33] and in a meta-analysis [34], the incidence of LBP was higher in smokers. Although the probability of contracting single and double diseases was insignificant for men who consumed alcohol, it was determined that they were 0.85% and 0.71% higher, respectively, and 0.53% and 1.15% higher for women. Again, a significant relationship was found between LBP and alcohol abusers [33].
As the consumption of one or more fruits per day boosts in individuals, the prevalence of single and dual diseases alleviates significantly in both sexes. For example, when compared with individuals consuming fruits less than once per day, in male individuals who consume one or more fruits per day, single and double disease burden significantly shrank by 2.46% and 2.18%, respectively, and in female individuals by 2.02% and 6.18%, respectively (P < 0.05 for all comparisons). In other words, the double disease burden of female individuals is approximately three times less than the single disease burden. In this context, female individuals who consume one or more fruits per day have a 2.83 times lower risk of catching dual disease than males. On the other hand, women who consume carbonated beverages have a significantly lower risk of developing single and dual diseases by 0.78% and 1.84%, respectively, than those who do not (P < 0.05 for all comparisons). Such findings are also compatible with the literature. In a recent study, higher daily consumption of fruits, whole grains, and dairy products was associated with a 20–26% lower probability of CSP (for all trends P < 0.028) [21].
Female individuals with a monthly income higher than 6900 Turkish Lira (TL) have a significantly lower risk of developing a single and dual disease by 1.36% and 3.00 points, respectively, when compared with females with a monthly income lower than 3400 TL (P < 0.05 for all comparisons). As the socioeconomic level of women increases, the probability of carrying both diseases shrinks. As the monthly income of women increases, the probability of developing a double disease decreases by 2.2 times compared to the probability of getting a single disease. A study conducted on a population over the age of 65 found that low socioeconomic status was associated with high LBP [24]. On the other hand, as the number of children aged 0–6 years increased in the family, the probability of developing single and dual diseases among women decreased significantly by 1.26% and 3.06%, respectively (P < 0.05 for all comparisons). A study stated that LBP was linearly associated with being married and increasing the number of children [22].
When compared with male individuals living in the Eastern Anatolian region, the prevalence of single and dual diseases in males living in the Istanbul, Aegean, Mediterranean, Western Anatolian, and Eastern Black Sea regions was significantly higher (4.72% and 4.50%, 5.92% and 6.18%, 2.52% and 2.23%, 5.00% 5.07% and 4.58% and 4.18%, respectively). (P < 0.05 for all comparisons). This result is compatible with the literature. Such a finding can be associated with the lower socioeconomic level and education level of those living in Eastern Anatolia in interregional comparisons in Turkey [35]. There is also a significant positive relationship between the probability of both male and female individuals having depression and the probability of developing a single or dual illness. Men with depression were more than 2.5 times more likely to have a single illness (9.63%) than women (3.73%), while women with a double illness were 1.5 times more likely to have a single illness (12.5% and 18.08%, respectively) (P < 0.05 for all comparisons). There is increasing evidence that pain problems increase the risk of depression. Depression is a strong and independent predictor of the onset of an episode of intense and/or disabling of these two diseases [36]. In another study, depression and somatization disorder had a significantly positive association with LBP [37]. According to a systematic review, initial symptoms of depression were found to worsen the prognosis of LBP [38].