Projected impact of population aging on non-communicable disease burden and costs in the Kingdom of Saudi Arabia, 2020-2030

BACKGROUND

The number of people aged greater than 65 years per 100 people aged 20-64 years is expected to almost double in The Kingdom of Saudi Arabia (KSA) between 2020 and 2030. We therefore aimed to quantify the growing non-communicable disease (NCD) burden in KSA between 2020 and 2030, and the impact this will have on the national health budget.

METHODS

Ten priority NCDs were selected: ischemic heart disease, stroke, type 2 diabetes, chronic obstructive pulmonary disease, chronic kidney disease, dementia, depression, osteoarthritis, colorectal cancer, and breast cancer. Age- and sex-specific prevalence was projected for each priority NCD between 2020 and 2030. Treatment coverage rates were applied to the projected prevalence estimates to calculate the number of patients incurring treatment costs for each condition. For each priority NCD, the average cost-of-illness was estimated based on published literature. The impact of changes to our base-case model in terms of assumed disease prevalence, treatment coverage, and costs of care, coming into effect from 2023 onwards, were explored.

RESULTS

The prevalence estimates for colorectal cancer and stroke were estimated to almost double between 2020 and 2030 (97% and 88% increase, respectively). The only priority NCD prevalence projected to increase by less than 60% between 2020 and 2030 was for depression (22% increase). It is estimated that the total cost of managing priority NCDs in KSA will increase from USD 19.8 billion in 2020 to USD 32.4 billion in 2030 (an increase of USD 12.6 billion or 63%). The largest USD value increases were projected for osteoarthritis (USD 4.3 billion), diabetes (USD 2.4 billion), and dementia (USD 1.9 billion). In scenario analyses, our 2030 projection for the total cost of managing priority NCDs varied between USD 29.2 billion - USD 35.7 billion.

CONCLUSIONS

Managing the growing NCD burden in KSA's aging population will require substantial healthcare spending increases over the coming years.

Racial differences in the association of subcutaneous and visceral fat on bone mineral content in prepubertal children

Total fat mass plays a significant role in determining bone mass, but the specific role of central adiposity independent of total fat mass has not been widely studied. Prepubertal (Tanner 1) children (n = 181; 65 boys, 116 girls, 7.8 +/- 1.5 years), including 99 Caucasians and 82 African Americans from Birmingham, Alabama, participated in this study. Body composition, including total body and trunk fat mass, and bone mineral content (BMC) were measured using dual-energy X-ray absorptiometry. Subcutaneous abdominal adipose tissue (SAAT) and intra-abdominal adipose tissue (IAAT) were determined by single-slice computed tomography (CT). After adjusting for gender, age, height, total fat, and lean mass, trunk weight was inversely correlated with BMC in Caucasians (r = -0.56, P < 0.0001) and in African Americans (r = -0.37, P < 0.05). In Caucasians, independent of gender, age, height, total fat, and lean mass, there was an inverse correlation between SAAT and BMC (r = -0.58, P < 0.0001) but no significant correlation between IAAT and BMC; in addition, SAAT explained 6% of the variance in BMC. In contrast, in African Americans, SAAT and BMC were not significantly correlated. However, while adjusting for gender, age, height, SAAT, total fat, and lean mass, an inverse association between IAAT and BMC was observed in African Americans (r = -0.50, P < 0.01); IAAT also explained 3% of the variance in BMC. These findings suggest that, in general, total abdominal weight is negatively associated with bone mass, but there appear to be racial differences with regard to the contributions of subcutaneous and visceral fat to BMC in prepubertal children.

Bone Mineral Density in Hispanic Women: Role of Aerobic Capacity, Fat-Free Mass, and Adiposity

Understanding the etiology of factors influencing bone mineral density (BMD) in Hispanic women for the prevention of osteoporosis was the aim of this investigation. Whole body BMD (WBBMD) of 39 Hispanic, premenopausal women aged 22 - 51 years was measured using dual-energy X-ray absorptiometry (DXA). Maximal aerobic capacity ((.-)VO(2max)) was determined by treadmill ergometry with direct measurement of oxygen consumption. Fat-free mass (FFM) and fat mass were estimated from two independent techniques, DXA and bioelectrical impedance analysis (BIA). A questionnaire was administered to determine weekly physical activity, age of menarche, oral contraceptive (OC) use, parity, and lactation. Factors with significant correlation to WBBMD were weight ( r = 0.74), body mass index ( r = 0.66), fat mass ( r = 0.68 - 0.69), FFM ( r = 0.55 - 0.65), percent fat ( r = 0.43 - 0.55), sagittal diameter ( r = 0.58), waist circumference ( r = 0.53), hip circumference ( r = 0.66) and weekly activity ( r = 0.40). Stepwise multiple linear regression revealed that 73 % of the variance in WBBMD is attributed to fat mass (55 %), FFM (10 %), and (.-)VO(2max) (8 %). When BIA was used instead of DXA in the regression, (.-)VO(2max) was no longer an independent predictor of WBBMD. Fat mass and FFM accounted for 43 % and 20 % of the variance in WBBMD, respectively, explaining a total of 63 % of the variance. The addition of age, age of menarche, weekly physical activity, OC use, parity, and lactation did not make significant contributions to the variance. The findings of this study suggest that fat mass is a stronger predictor of bone mineral density than fat-free mass to BMD; aerobic capacity is another important predictor of BMD in Hispanic premenopausal women.

Central Adiposity, Aerobic Fitness, and Blood Pressure in Premenopausal Hispanic Women

Hispanics comprise one of the fastest-growing segments of the U.S. population. Mexican-American adults are more likely to be overweight, physically inactive, diabetic, and to have higher levels of hypertension than are white adults. However, studies addressing the relationship between physical fitness and coronary artery disease (CAD) risk factors among Mexican-Americans are much less conclusive. Therefore, understanding the etiology of factors influencing resting systolic (SBP) and diastolic blood pressure (DBP) in Hispanic women was the aim of this investigation. SBP, DBP, peak oxygen uptake (peak VO (2)), weekly physical activity, waist (WC) and hip circumference, blood glucose, and levels of plasma lipids (triglyceride, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol) of 39 Hispanic women age 22 - 51 years were measured. Factors with significant correlation to SBP were age, WC, sagittal diameter, and weight. Similarly, significant correlations were observed between anthropometric indices, age, and DBP. Peak VO (2) ( r = - 0.53, p < 0.01) and heart rate at maximal effort ( r = - 0.34, p </= 0.05) were inversely associated to DBP. There was also a strong inverse correlation ( r = - 0.53, p < 0.01) between peak VO (2) and CAD risk profile (created from one or the combination of: hypertension, obesity, hyperglycemia, dyslipidemia, smoking). Stepwise multiple linear regression revealed that 33 % of the variance in SBP is attributed to age (25 %), and WC (8 %), while DBP is explained by WC alone (26 %). The addition of peak VO (2) did not make significant contributions to the variances in SBP or DBP. The findings of this study suggest that central adiposity is an important predictor of resting blood pressure in Hispanic women. The inverse association between aerobic fitness and diastolic blood pressure as well as CAD risk factors suggests that recommendations regarding prevention of hypertension in this population should be based on the interrelationships between physical fitness and obesity.

Ethnic differences in ovulatory function in nulliparous women

African-American women have a long-standing approximately 20% higher breast cancer incidence rate than USA White women under age 40 while rates among Latinas are lower than those of Whites. The reasons for this are not clear, however they may be due to ethnic differences in circulating oestradiol and progesterone levels. In a cross-sectional study, we investigated whether anovulation frequency and circulating serum oestradiol and/or progesterone levels vary among normally cycling nulliparous African-American (n=60), Latina (n=112) and non-Latina White (n=69) women. Blood and urine specimens were collected over two menstrual cycles among healthy 17- to 34-year-old women. Frequency of anovulation was greater among White women (nine out of 63, 14.3%) than African-American women (four out of 56, 7.1%) or Latina women (seven out of 102, 6.9%), although these differences were not statistically significant. African-American women had 9.9% (P=0.26) higher follicular phase oestradiol concentrations than Latina women and 17.4% (P=0.13) higher levels than White women. African-American women also had considerably higher levels of luteal phase oestradiol (vs Latinas, +9.4%, P=0.14; vs Whites, +25.3%, P=0.003) and progesterone (vs Latinas, +15.4%, P=0.07; vs Whites, +36.4%, P=0.002). Latina women were also observed to have higher follicular oestradiol, and luteal oestradiol and progesterone levels than White women (follicular oestradiol: +6.8%, P=0.48; luteal oestradiol: +14.6%, P=0.04; luteal progesterone: +18.2%, P=0.06). These results suggest that exposure to endogenous steroid hormones may be greater for young African-American and Latina women than for Whites.