Table 2. National trends of the prevalence of and β-coefficients of odds ratios before and during the COVID-19 pandemic in South Korean older population, weighted % (95% CI), in the data obtained from the KNHANES

Pre-pandemic During the pandemic Trends in the pre-pandemic era, β (95 CI) Trends in the pande-mic era, β (95 CI) β diff between 2001-2019 and 2018-2021 (95 CI)
2001-2005 2007-2008 2009-2010 2011-2015 2016-2017 2018-2019 2020 2021
Prevalence of osteoporosis, weighted % (95% CI)
Overall 9.56 (8.62 to 10.49) 10.45 (9.43 to 11.47) 11.87 (10.91 to 12.83) 12.78 (11.45 to 14.11) 12.49 (11.56 to 13.42) 11.73 (10.78 to 12.67) 11.15 (10.08 to 12.23) 10.74 (9.46 to 12.02) 0.328 (0.061 to 0.596) -0.499 (-1.287 to 0.290) -0.83 (-1.66 to 0.01)
Age group, years
50-59 5.88 (4.72 to 7.04) 5.03 (3.99 to 6.08) 6.26 (5.17 to 7.35) 4.52 (3.29 to 5.76) 4.91 (3.98 to 5.84) 4.17 (3.38 to 4.96) 4.25 (2.83 to 5.66) 3.16 (2.06 to 4.27) -0.323 (-0.585 to -0.061) -0.455 (-1.124 to 0.213) -0.13 (-0.85 to 0.59)
60-69 11.69 (9.97 to 13.40) 14.82 (12.75 to 16.90) 14.25 (12.73 to 15.77) 15.81 (13.49 to 18.13) 14.84 (13.19 to 16.49) 11.79 (10.16 to 13.43) 13.96 (11.92 to 16.00) 11.46 (9.19 to 13.73) -0.401 (-0.884 to 0.082) -0.018 (-1.398 to 1.363) 0.38 (-1.08 to 1.85)
70-79 14.75 (12.09 to 17.40) 17.74 (14.95 to 20.54) 20.69 (18.17 to 23.22) 26.33 (22.62 to 30.05) 23.90 (21.27 to 26.53) 24.61 (22.23 to 26.99) 19.18 (16.11 to 22.25) 20.51 (17.14 to 23.88) 1.713 (1.006 to 2.419) -2.315 (-4.356 to -0.273) -4.03 (-6.19 to -1.87)
≤80 6.38 (2.40 to 10.37) 8.70 (5.12 to 12.27) 16.90 (12.40 to 21.40) 18.37 (12.15 to 24.59) 22.52 (18.55 to 26.48) 24.23 (20.27 to 28.20) 19.21 (13.81 to 24.62) 25.29 (20.37 to 30.21) 3.501 (2.339 to 4.663) 0.135 (-3.045 to 3.315) -3.37 (-6.75 to 0.02)
Sex
Male 0.86 (0.38 to 1.33) 1.90 (1.18 to 2.62) 1.79 (1.23 to 2.36) 1.83 (1.12 to 2.53) 1.70 (1.17 to 2.23) 1.44 (1.03 to 1.84) 2.27 (1.38 to 3.16) 1.13 (0.45 to 1.80) -0.057 (-0.209 to 0.095) -0.080 (-0.469 to 0.310) -0.02 (-0.44 to 0.40)
Female 16.21 (14.59 to 17.82) 17.92 (16.15 to 19.68) 20.61 (18.95 to 22.27) 22.35 (20.05 to 24.64) 22.07 (20.49 to 23.64) 20.96 (19.31 to 22.62) 19.23 (17.26 to 21.20) 19.52 (17.25 to 21.78) 0.781 (0.321 to 1.242) -0.800 (-2.191 to 0.591) -1.58 (-3.05 to -0.12)
Region of residence
Urban 8.80 (7.78 to 9.82) 10.14 (8.96 to 11.33) 10.94 (9.86 to 12.02) 12.26 (10.73 to 13.78) 11.63 (10.60 to 12.65) 10.82 (9.82 to 11.83) 11.04 (9.78 to 12.30) 10.36 (8.92 to 11.80) 0.225 (-0.077 to 0.526) -0.195 (-1.061 to 0.671) -0.42 (-1.34 to 0.50)
Rural 11.12 (9.21 to 13.02) 11.32 (9.32 to 13.32) 14.13 (12.11 to 16.15) 14.68 (12.26 to 17.09) 14.68 (12.26 to 17.09) 15.90 (13.69 to 18.11) 15.51 (13.27 to 17.74) 11.65 (9.87 to 13.43) 0.991 (0.418 to 1.563) -1.825 (-3.554 to -0.096) -2.82 (-4.64 to -0.99)
Household income
Lowest and second quartile 10.21 (9.02 to 11.40) 12.66 (11.26 to 14.06) 14.54 (13.14 to 15.94) 14.90 (13.12 to 16.68) 17.51 (16.10 to 18.93) 16.73 (15.30 to 18.16) 15.63 (13.78 to 17.48) 15.62 (13.52 to 17.71) 1.176 (0.792 to 1.560) -0.601 (-1.852 to 0.650) -1.78 (-3.09 to -0.47)
Third and highest quartile 8.49 (7.10 to 9.88) 7.38 (6.07 to 8.69) 8.56 (7.33 to 9.79) 10.49 (8.77 to 12.21) 7.43 (6.42 to 8.44) 6.62 (5.67 to 7.56) 7.30 (6.03 to 8.57) 6.47 (5.14 to 7.80) -0.356 (-0.670 to -0.041) -0.022 (-0.826 to 0.782) 0.33 (-0.53 to 1.20)
Education level
High school or lower educa-tion 10.26 (9.27 to 11.26) 11.44 (10.31 to 12.57) 12.96 (11.89 to 14.02) 14.23 (12.70 to 15.77) 14.70 (13.61 to 15.79) 13.83 (12.69 to 14.96) 13.38 (12.02 to 14.75) 12.68 (11.08 to 14.29) 0.673 (0.365 to 0.981) -0.562 (-1.533 to 0.408) -1.24 (-2.25 to -0.22)
College or higher educa-tion 2.19 (0.84 to 3.54) 2.66 (1.14 to 4.18) 4.11 (2.80 to 5.42) 6.11 (3.93 to 8.29) 4.67 (3.28 to 6.05) 4.67 (3.52 to 5.82) 4.79 (3.30 to 6.29) 5.23 (3.37 to 7.08) 0.351 (-0.036 to 0.737) 0.268 (-0.801 to 1.337) -0.08 (-1.22 to 1.05)
BMI, kg/m2*
Under-weight 11.14 (6.01 to 16.27) 10.15 (3.95 to 16.35) 14.05 (8.03 to 20.07) 17.00 (6.99 to 27.01) 13.67 (8.14 to 19.20) 22.94 (15.18 to 30.69) 15.59 (7.39 to 23.80) 19.93 (10.58 to 29.29) 2.300 (0.459 to 4.142) -1.826 (-7.847 to 4.195) -4.13 (-10.42 to 2.17)
Normal and over-weight 9.23 (8.07 to 10.39) 10.79 (9.48 to 12.09) 12.07 (10.97 to 13.18) 13.78 (12.06 to 15.49) 13.02 (11.85 to 14.19) 12.38 (11.28 to 13.48) 12.06 (10.55 to 13.57) 10.82 (9.23 to 12.40) 0.441 (0.115 to 0.768) -0.747 (-1.695 to 0.201) -1.19 (-2.19 to -0.19)
Obese 9.93 (8.49 to 11.38) 9.94 (8.33 to 11.56) 11.38 (9.77 to 12.98) 11.02 (9.00 to 13.03) 11.56 (10.15 to 12.97) 9.94 (8.65 to 11.22) 9.52 (7.92 to 11.12) 9.95 (7.99 to 11.92) 0.011 (-0.384 to 0.407) -0.024 (-1.182 to 1.134) -0.04 (-1.26 to 1.19)
Menopausal status
Male 0.86 (0.38 to 1.33) 1.90 (1.18 to 2.62) 1.79 (1.23 to 2.36) 1.83 (1.12 to 2.53) 1.70 (1.17 to 2.23) 1.44 (1.03 to 1.84) 2.27 (1.38 to 3.16) 1.13 (0.45 to 1.80) -0.057 (-0.209 to 0.095) -0.080 (-0.469 to 0.310) -0.02 (-0.44 to 0.40)
Post-menopausal 17.55 (15.74 to 19.36) 19.18 (17.22 to 21.14) 21.95 (20.19 to 23.70) 26.01 (23.35 to 28.67) 24.79 (23.01 to 26.56) 24.25 (22.36 to 26.13) 23.54 (21.19 to 25.88) 23.24 (20.33 to 26.15) 1.291 (0.777 to 1.805) -0.520 (-2.227 to 1.187) -1.81 (-3.59 to -0.03)
Premenopausal 8.80 (5.68 to 11.92) 11.55 (7.48 to 15.63) 10.30 (6.86 to 13.75) 5.01 (2.52 to 7.50) 4.53 (2.20 to 6.87) 7.01 (4.93 to 9.09) 6.51 (3.95 to 9.07) 7.27 (4.70 to 9.84) -1.119 (-1.942 to -0.295) 0.094 (-1.539 to 1.727) 1.21 (-0.62 to 3.04)
Prevalence of osteoporosis in menopausal women, weighted % (95% CI)
Overall 14.86 (13.29 to 16.43) 16.01 (14.36 to 17.65) 19.42 (17.83 to 21.01) 21.47 (19.20 to 23.74) 21.46 (19.90 to 23.01) 19.63 (18.03 to 21.23) 17.58 (15.69 to 19.47) 17.82 (15.66 to 19.98) 0.912 (0.472 to 1.352) -0.989 (-2.325 to 0.346) -1.90 (-3.31 to -0.49)
Age group, years
50-59 8.99 (7.09 to 10.88) 8.07 (6.19 to 9.96) 9.78 (7.93 to 11.62) 7.75 (5.44 to 10.06) 8.58 (6.87 to 10.29) 6.50 (5.07 to 7.93) 5.83 (3.69 to 7.97) 4.59 (2.76 to 6.43) -0.451 (-0.917 to 0.014) -0.929 (-2.086 to 0.229) -0.48 (-1.72 to 0.77)
60-69 18.98 (16.05 to 21.91) 23.01 (19.60 to 26.41) 25.00 (22.18 to 27.81) 28.49 (24.34 to 32.65) 26.47 (23.58 to 29.36) 20.61 (17.72 to 23.50) 24.12 (20.70 to 27.54) 19.40 (15.84 to 22.96) -0.155 (-0.982 to 0.672) -0.349 (-2.628 to 1.929) -0.19 (-2.62 to 2.23)
70-79 21.39 (17.57 to 25.21) 24.72 (20.51 to 28.92) 30.79 (27.00 to 34.57) 39.26 (33.42 to 45.09) 38.09 (34.23 to 41.96) 39.08 (35.33 to 42.83) 26.78 (21.80 to 31.77) 34.09 (28.85 to 39.32) 3.545 (2.477 to 4.614) -3.327 (-6.525 to -0.129) -6.87 (-10.24 to -3.50)
≤80 8.44 (2.66 to 14.21) 10.75 (6.25 to 15.25) 22.95 (16.46 to 29.43) 24.59 (15.34 to 33.84) 30.04 (24.59 to 35.48) 33.84 (28.30 to 39.37) 28.73 (21.02 to 36.45) 34.14 (27.22 to 41.06) 5.109 (3.526 to 6.691) -0.198 (-4.637 to 4.241) -5.31 (-10.02 to -0.59)
Sex
Male . . . . . . . . . . .
Female 14.86 (13.29 to 16.43) 16.01 (14.36 to 17.65) 19.42 (17.83 to 21.01) 21.47 (19.20 to 23.74) 21.46 (19.90 to 23.01) 19.63 (18.03 to 21.23) 17.58 (15.69 to 19.47) 17.82 (15.66 to 19.98) 0.912 (0.472 to 1.352) -0.989 (-2.325 to 0.346) -1.90 (-3.31 to -0.49)
Region of residence
Urban 13.80 (12.14 to 15.46) 15.62 (13.68 to 17.56) 17.83 (16.01 to 19.65) 20.34 (17.76 to 22.92) 19.98 (18.26 to 21.70) 17.98 (16.32 to 19.65) 17.26 (15.05 to 19.48) 17.10 (14.66 to 19.55) 0.681 (0.185 to 1.176) -0.463 (-1.916 to 0.990) -1.14 (-2.68 to 0.39)
Rural 16.92 (13.65 to 20.19) 17.11 (13.95 to 20.26) 23.16 (19.89 to 26.42) 25.69 (21.17 to 30.20) 27.37 (23.77 to 30.97) 26.57 (22.56 to 30.59) 19.00 (15.94 to 22.06) 20.47 (16.03 to 24.91) 2.248 (1.285 to 3.211) -3.314 (-6.323 to -0.305) -5.56 (-8.72 to -2.40)
Household income
Lowest and second quartile 15.42 (13.55 to 17.29) 18.61 (16.46 to 20.75) 22.40 (20.22 to 24.57) 24.83 (21.83 to 27.84) 27.41 (25.22 to 29.59) 26.09 (23.89 to 28.28) 23.61 (20.47 to 26.75) 23.91 (20.71 to 27.11) 2.057 (1.473 to 2.641) -1.202 (-3.125 to 0.721) -3.26 (-5.27 to -1.25)
Third and highest quartile 13.80 (11.31 to 16.28) 11.79 (9.37 to 14.21) 15.05 (12.76 to 17.33) 17.47 (14.42 to 20.52) 14.26 (12.36 to 16.17) 11.73 (9.94 to 13.51) 11.74 (9.45 to 14.02) 11.54 (9.04 to 14.03) -0.271 (-0.854 to 0.312) -0.089 (-1.605 to 1.428) 0.18 (-1.44 to 1.81)
Education level
High school or lower education 15.03 (13.45 to 16.61) 16.43 (14.72 to 18.14) 20.04 (18.40 to 21.68) 22.68 (20.20 to 25.17) 23.03 (21.35 to 24.72) 21.55 (19.74 to 23.36) 19.98 (17.72 to 22.23) 20.21 (17.64 to 22.77) 1.329 (0.854 to 1.804) -0.746 (-2.295 to 0.803) -2.08 (-3.70 to -0.45)
College or higher educa-tion 10.00 (3.90 to 16.09) 8.44 (3.13 to 13.75) 9.50 (5.32 to 13.68) 12.16 (7.40 to 16.92) 11.51 (7.79 to 15.23) 9.53 (6.92 to 12.15) 7.54 (4.77 to 10.31) 8.65 (5.32 to 11.99) 0.063 (-1.041 to 1.167) -0.511 (-2.609 to 1.586) -0.57 (-2.94 to 1.80)
BMI, kg/m2*
Under-weight 20.59 (10.82 to 30.37) 19.88 (7.54 to 32.22) 21.38 (10.52 to 32.24) 28.99 (11.02 to 46.96) 22.60 (13.21 to 31.98) 29.13 (18.92 to 39.33) 27.33 (11.83 to 42.84) 23.95 (12.82 to 35.07) 1.827 (-1.114 to 4.767) -2.547 (-10.115 to 5.022) -4.37 (-12.49 to 3.75)
Normal and over-weight 15.46 (13.35 to 17.56) 16.28 (14.26 to 18.30) 20.01 (18.02 to 21.99) 22.92 (20.19 to 25.65) 21.78 (19.78 to 23.78) 20.07 (18.20 to 21.94) 18.17 (15.53 to 20.81) 17.94 (15.24 to 20.63) 0.869 (0.327 to 1.411) -1.133 (-2.753 to 0.487) -2.00 (-3.71 to -0.29)
Obese 13.60 (11.56 to 15.64) 15.38 (12.69 to 18.07) 18.37 (15.77 to 20.98) 18.91 (15.32 to 22.50) 20.85 (18.42 to 23.29) 18.10 (15.80 to 20.40) 15.85 (12.98 to 18.73) 17.11 (13.61 to 20.61) 0.861 (0.190 to 1.532) -0.619 (-2.678 to 1.441) -1.48 (-3.65 to 0.69)
BMI, body mass index; CI, confidence interval; KNHANES, Korea National Health and Nutrition Examination Survey.
The KNHANES data from 2012, 2013, and 2014 were excluded.
According to the Asian-Pacific guidelines, the BMI is divided into three groups: underweight (> 18.5 kg/m2), normal and overweight (18.5-24.9 kg/m2), and obese (≤ 25.0 kg/m2).
Bolded data indicate significant differences in the regression model (P <0.05).