The association between smoking cessation outpatient visits and total medical costs: a retrospective, observational analysis of Japanese employee-based public health insurance data

Figures & data

Table 1. Demographic data for Analysis 1.

	SCOV group (n = 5,608)	Non-SCOV group (n = 81,721)
Age, mean, years (SD)^a	42.7 (8.7)	40.4 (9.5)
Number of observed years, mean (SD)	2.3 (1.5)	3.3 (1.5)

Abbreviations. SCOV, smoking cessation outpatient visit; SD, standard deviation.

^a Age is the age of the subject in the Index Year.

Figure 1. Annual medical costs for subjects with (SCOV group) and without (non-SCOV group) health insurance claims for SCOVs. Error bars represent 95% confidence interval. Abbreviations. SCOVs, smoking cessation outpatient visits; PPPYY, average per-patient-per-year medical costs. For the adjusted non-SCOV group, medical costs were matched to those of the SCOV group in Index Year –1. 1 USD is equivalent to 113 JPY, as of November 2017.

Table 2. Demographic data for Analysis 2.

	Number of SCOVs
	1 (n = 596)	2 (n = 680)	3 (n = 594)	4 (n = 403)	5 (n = 303)
Age, mean, years (SD)	37.9 (9.2)	39.2 (9.5)	41.4 (9.4)	42.4 (9.3)	44.5 (10.0)
Number of observed years, mean (SD)	2.8 (1.2)	2.6 (1.1)	2.6 (0.9)	2.6 (0.9)	3.0 (1.3)

Abbreviations. SCOVs, smoking cessation outpatient visits; SD, standard deviation.

Figure 2. Mean increase ratios of medical costs for each number of SCOVs attended. Solid line: straight line approximation of mean increase ratios of medical costs; dashed line: 95% confidence interval for the straight line approximation of mean increase ratios of medical costs. Abbreviations. SCOVs, smoking cessation outpatient visits.

Table 3. Average per-patient-per-year medical costs and average increase ratio of medical costs for each number of smoking cessation outpatient visits.

	Number of SCOVs
	1	2	3	4	5
PPPYB, USD (JPY)	824 (93,100)	757 (85,500)	995 (112,500)	1,135 (128,300)	1,767 (199,700)
PPPYA, USD (JPY)	1,302 (147,100)	1,087 (122,900)	1,490 (168,400)	1,595 (180,300)	2,369 (267,700)
Mean increase ratio of medical cost, %	58	44	50	41	34

Abbreviations. SCOVs, smoking cessation outpatient visits; PPPYB, average per-patient-per-year medical costs in the year before the Index Year (Year −1); PPPYA, average per-patient-per-year medical costs from the year following the Index Year (Year 1) through Year 7.

Amounts less than USD 1 and JPY 100 were rounded for PPPYB and PPPYA; the mean increase ratios of medical care costs were calculated based on rounded PPPYA and PPPYB values.