Table 2. Patient demographic characteristics; #60 controls and 20 patients treated with HBOT; COPD – chronic obstructive pulmonary disease; HBOT – hyperbaric oxygen treatment; NR − not reported .

Study	n	Female n	Age (years)	Ethnicity	Comorbidities
Chen[25]	5	1	Mean 47 Range 24−69	Chinese: 5	Hypertension: 1 Cardiovascular disease: 1
Gorenstein[30]	80#	7	HBOT: Median 58 Range 30−79 Control: Median 62 Range 24−80	White: 23 Black: 13 Asian: 7 Other: 37	Hypertension: 40 (50%) Diabetes: 24 (30%) Cardiovascular disease: 8 (10%) COPD: 4 (5%)
Guo[29]	2	0	57 and 64	Chinese: 2	Hypertension: 1 Diabetes: 1 Cardiovascular disease: 1
Qian[26]	4	0	Range 56−67	Chinese: 4	NR
Thibodeaux[27]	5	4	Median 48 Range 39−63	White: 2 Black: 3	Obese: 4 Hypertension: 4 Diabetes: 3
Zhong [28]	1	0	87	Chinese	Cardiovascular disease COPD