Sociodemographic and clinical factors affecting the quality of life of patients with chronic obstructive pulmonary disease

Figures & data

Table 1 Clinical characteristics of the studied COPD patients

Spirometry	X±SD	Min–Max
FEV1 (L)	1.36±0.7	0.51–3.51
FEV1 (%N)	48±15.9	15–84
Ratio of FEV1 to FVC	0.62±0.18	0.42–1.24
Characteristics	N	%
Duration of the disease
0–5 years	49	49.0
5–10 years	29	29.0
10–15 years	13	13.0
>15 years	9	9.0
Disease severity by GOLD
I	3	3.0
II	37	37.0
III	52	52.0
IV	7	7.0
Smoking cigarettes
Yes	49	49.0
No	51	51.0
Duration of smoking
0–5 years	11	11.0
5–10 years	8	8.0
10–15 years	13	13.0
>15 years	17	17.0
Frequency of dyspnea exacerbations during last month
None	4	4.0
Once a day	12	12.0
More often than twice a day	18	18.0
Several times a week	25	25.0
Only after physical effort	41	41.0
Frequency of awakening due to COPD symptoms during last month
None	16	16.0
Once a week	33	33.0
Three nights a week or more often	52	51.0
Hospitalization due to exacerbation of COPD during the last 12 months
Yes	61	61.0
No	39	39.0
Ability of taking inhaled medications
Yes	67	67.0
No	33	33.0
The use of oxygen at home
Yes	19	19.0
No	81	81.0

Abbreviations: GOLD, Global Obstructive Lung Disease; Max, maximum value; Min, minimum value; N, number of participants; X, mean value.

Table 2 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of women and men

Scale	Female (n=34)				Male (n=66)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	52.12	20.76	58	6–83	52.20	23.23	57	8–95	0.799
Mental dimension	33.32	13.93	38	1–56	31.56	13.11	35	4–56	0.396
SGRQ
Symptoms	55.10	18.08	58	6–89	60.01	22.91	60	6–97	0.407
Activity	45.57	14.95	48	5–73	49.63	18.95	49	5–81	0.407
Impact	46.50	26.32	51	0–95	45.41	28.90	50	0–99	0.945
Global score	50.28	23.22	51	1–91	50.03	25.41	54	2–97	0.968
AIS
Score	21.71	5.95	21	10–35	22.83	6.63	23	8–35	0.327

Abbreviations: AIS, Acceptance of Illness Scale; LIA, the level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 3 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients at the age of ≥60 years

Scale	Age <60 years (n =53)				Age >60 years (n =47)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	40.74	21.62	43	6–79	65.06	14.93	67	30–95	<0.001
Mental dimension	27.58	13.83	25	1–52	37.32	10.77	38	14–56	<0.001
SGRQ
Symptoms	50.40	20.69	52	6–97	67.29	18.69	68	29–96	<0.05
Activity	41.68	17.11	43	5–81	55.65	15.46	56	24–79	<0.001
Impact	34.22	27.56	34	0–95	58.82	22.17	58	2–99	<0.001
Global score	39.69	24.41	40	1–91	61.88	18.94	61	8–97	<0.001
AIS
Score	24.25	6.08	24	10–35	20.43	6.21	19	8–35	0.001

Note: P-values in bold indicate a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, the level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 4 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients with higher education and other higher

Scale	Other education (n =69)				Higher education (n =31)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	57.10	19.34	63	6–95	41.19	24.81	46	8–86	0.003
Mental dimension	34.41	12.59	37	1–56	27.16	13.83	29	4–49	0.013
SGRQ
Symptoms	60.01	20.69	60	6–97	54.61	22.88	52	6–95	0.186
Activity	49.63	17.11	50	5–81	45.17	18.92	43	5–79	0.186
Impact	50.46	23.91	52	0–99	35.38	33.39	25	0–95	0.018
Global score	53.95	21.08	54	1–97	41.59	29.61	40	3–91	0.061
AIS
Score	21.33	6.23	21	8–35	24.94	6.15	24	10–35	0.013

Note: P-values in bold indicate a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, the level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 5 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients living in the city and in the countryside

Scale	City (n=85)				Countryside (n =15)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	50.98	22.62	56	6–95	58.93	19.84	63	21–92	0.243
Mental dimension	31.08	13.02	34	1–56	38.27	14.02	45	11–54	0.023
SGRQ
Symptoms	58.16	22.34	58	6–97	59.33	15.86	60	27–96	0.817
Activity	48.10	18.47	48	5–81	49.07	13.12	50	22–79	0.817
Impact	43.82	27.24	48	0–99	56.90	30.12	66	0–97	0.061
Global score	48.43	24.27	51	1–97	59.68	24.89	62	4–92	0.081
AIS
Score	22.44	6.62	23	8–35	22.53	5.19	23	12–31	0.919

Note: P-value in bold indicates a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, the level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 6 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients who have been diagnosed with COPD up to 5 years prior to or later

Scale	Diagnosis < 5 years (n=49)				Diagnosis > 5 years (n=51)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	42.73	23.12	46	8–83	61.24	17.38	65	6–95	<0.001
Mental dimension	28.94	13.81	27	4–56	35.25	12.24	38	1–56	0.026
SGRQ
Symptoms	52.51	19.58	55	6–88	63.94	21.81	62	6–97	0.005
Activity	43.43	16.19	45	5–73	52.88	18.04	51	5–81	0.005
Impact	34.76	28.05	34	0–95	56.37	23.55	58	0–99	<0.001
Global score	41.44	25.30	43	2–91	58.45	20.89	58	1–97	0.001
AIS
Score	24.82	6.05	25	10–35	20.18	5.94	19	8–35	<0.001

Note: P-values in bold indicate a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, the level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 7 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients who are active smokers and non-smokers

Scale	Active smokers (n =49)				Non-smokers (n =51)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	52.88	24.40	58	8–95	51.49	20.35	56	6–92	0.510
Mental dimension	32.24	14.00	36	4–56	32.08	12.83	35	1–54	0.997
SGRQ
Symptoms	61.91	22.81	58	6–97	54.91	19.62	59	6–96	0.170
Activity	51.20	18.86	48	5–81	45.41	16.23	49	5–79	0.170
Impact	49.49	29.64	54	0–99	42.22	25.96	39	0–97	0.109
Global score	52.56	26.59	58	3–97	47.77	22.48	47	1–92	0.160
AIS
Score	21.24	7.09	20	8–35	23.61	5.48	24	10–35	0.073

Abbreviations: X, mean value; SD, standard deviations; Me, median value; P, the level of significance; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; AIS, Acceptance of Illness Scale; QOL, quality of life; LIA, the level of illness acceptance.

Table 8 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients with normal and abnormal BMI

Scale	Normal BMI (n =40)				Abnormal BMI (n =60)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	52.63	19.56	56	6–83	51.87	24.14	59	8–95	0.894
Mental dimension	34.40	13.22	39	1–56	30.67	13.33	33	4–56	0.130
SGRQ
Symptoms	58.82	19.44	59	6–92	58.01	22.81	56	6–97	0.786
Activity	48.65	16.07	49	5–77	47.98	18.86	47	5–81	0.786
Impact	48.05	27.11	53	0–95	44.27	28.58	49	0–99	0.506
Global score	52.32	23.29	57	1–91	48.65	25.47	51	3–97	0.425
AIS
Score	22.28	5.99	22	12–35	22.57	6.71	24	8–35	0.622

Abbreviations: AIS, Acceptance of Illness Scale; BMI, body mass index; LIA, the level of illness acceptance; Me, median value; P, level of significance; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; QOL, quality of life; X, mean value.

Table 9 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients claiming a proper or the lack of support from relatives

Scale	Proper support (n =78)				Lack of support (n =22)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	47.63	22.47	49	6–86	68.27	12.18	68	38–95	<0.001
Mental dimension	29.24	12.94	30	1–56	42.50	9.08	44	19–56	<0.001
SGRQ
Symptoms	55.90	21.16	56	6–97	66.96	20.55	65	6–96	0.015
Activity	46.24	17.50	46	5–81	55.38	16.99	54	5–79	0.015
Impact	39.86	26.56	44	0–91	66.80	22.27	62	22–99	<0.001
Global score	44.65	23.49	46	1–90	69.49	17.87	69	35–97	<0.001
AIS
Score	23.15	6.52	24	10–35	19.95	5.38	19	8–29	0.039

Note: P-values in bold indicate a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 10 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients with or without comorbidities

Scale	Presence of comorbidities (n =56)				Absence of comorbidities (n =44)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	63.54	15.09	65	28–95	37.70	21.75	39	6–72	<0.001
Mental dimension	37.93	10.14	39	14–56	24.82	13.43	22	1–52	<0.001
SGRQ
Symptoms	69.06	17.24	68	29–97	44.69	18.33	48	6–82	<0.001
Activity	57.12	14.26	56	24–81	36.96	15.16	39	5–67	<0.001
Impact	58.98	20.53	58	19–99	28.98	27.21	25	0–95	<0.001
Global score	61.87	17.23	61	29–97	35.16	24.52	38	1–91	<0.001
AIS
Score	20.02	5.62	19	8–35	25.55	6.03	26	10–35	<0.001

Note: P-values in bold indicate a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 11 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients with positive and negative family history of respiratory diseases

Scale	Positive family history (n =48)				Negative family history (n =52)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	57.71	21.43	63	6–95	47.06	22.09	49	8–83	0.019
Mental dimension	32.98	12.89	36	1–56	31.40	13.84	36	4–56	0.704
SGRQ
Symptoms	63.89	22.12	61	6–97	53.22	19.61	55	6–92	0.018
Activity	52.84	18.29	50	5–81	44.01	16.22	45	5–77	0.018
Impact	52.46	27.10	53	0–99	39.62	27.50	44	0–97	0.028
Global score	56.14	23.81	57	1–97	44.56	24.16	45	2–92	0.021
AIS
Score	20.94	6.29	20	8–35	23.85	6.24	24	10–35	0.020

Note: P-values in bold indicate a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Table 12 Comparison of the statistical characteristics of particular dimensions of the general and specific QOL and LIA in the subgroups of patients undertaking oxygen therapy or not

Scale	Presence of oxygen therapy (n =19)				Lack of oxygen therapy (n =81)				P-value
	X	SD	Me	Range	X	SD	Me	Range
SF-36
Physical dimension	73.47	10.43	70	57–95	47.17	21.42	50	6–83	<0.001
Mental dimension	43.26	7.32	44	28–56	29.56	13.13	30	1–56	<0.001
SGRQ
Symptoms	78.71	13.51	83	51–96	53.56	20.13	55	6–97	<0.001
Activity	65.10	11.17	69	42–79	44.30	16.65	46	5–81	<0.001
Impact	72.68	16.54	72	34–99	39.47	26.29	43	0–97	<0.001
Global score	72.01	15.15	72	37–97	44.98	23.56	46	1–92	<0.001
AIS
Score	18.26	5.08	18	8–27	23.43	6.31	24	10–35	0.001

Note: P-values in bold indicate a significant difference.

Abbreviations: AIS, Acceptance of Illness Scale; LIA, level of illness acceptance; Me, median value; P, level of significance; QOL, quality of life; SD, standard deviations; SF-36, Short Form-36 Health Survey; SGRQ, St George’s Respiratory Questionnaire; X, mean value.

Data availability

The authors confirm that all data underlying the findings described in this manuscript is fully available to all interested researchers upon request.