What role may symptoms play in the diagnosis of airflow limitation?

Figures & data

Table I.  Characteristics of the 3954 participants in the study.

	Women		Men
	n	%	n	%
Total	2154	54.5	1800	45.5
Age (years)
60–69	1152	53.5	957	53.2
70–79	889	41.3	748	41.6
80 +	113	5.2	95	5.3
Smoking habit^1
Never smoker	999	46.9	327	18.3
Ex-smoker	633	29.7	1043	58.3
Current smoker	498	23.4	419	23.4
Body mass index (BMI)
< 30	1636	76.0	1492	82.9
≥ 30	518	24.0	308	17.1
Airflow limitation
Any airflow limitation^2	333	15.5	375	20.8
Severe airflow limitation^3	73	3.4	88	4.9
Reported symptoms
Wheezing	483	22.4	437	24.3
Dyspnoea on unhurried walking	88	4.1	55	3.1
Dyspnoea on quick walking	1044	48.5	834	46.3
Daily cough in periods	346	16.1	407	22.6
Daily cough with phlegm	227	10.5	295	16.4
Chronic cough with phlegm	127	5.9	183	10.2

Notes: ¹Missing data in 24 women and 11 men. ²Defined as FEV1/FVC < 70% for persons 69 years and younger and FEV1/FVC < 65% for persons 70 years and older. ³In addition FEV1 < 50% predicted according to the equation of Langhammer.

Table II.  Frequency of reported symptoms (%) by smoking status in 2130 women and 1789 men aged 60 years or more.

	Women			Men
Reported symptoms	Never smoker	Ex-smoker^1	Smoker^2	Never smoker	Ex-smoker^1	Smoker^2
Wheezing	16.8	25.8 ^p = 0.000	29.3 ^p = 0.202	11.9	22.7 ^p = 0.000	37.7 ^p = 0.000
Dyspnoea on unhurried walking	4.1	3.9 ^p = 1.000	4.2 ^p = 0.880	1.5	3.0 ^p = 0.232	4.3 ^p = 0.202
Dyspnoea on quick walking	45.7	50.7 ^p = 0.053	51.4 ^p = 0.857	33.3	47.3 ^p = 0.000	53.7 ^p = 0.028
Daily cough in periods	12.3	13.6 ^p = 0.449	26.9 ^p = 0.000	15.0	17.8 ^p = 0.274	40.3 ^p = 0.000
Daily cough with phlegm	6.4	9.6 ^p = 0.022	20.1 ^p = 0.000	10.1	13.2 ^p = 0.150	28.9 ^p = 0.000
Chronic cough with phlegm	2.9	6.0 ^p = 0.003	11.8 ^p = 0.001	6.7	7.9 ^p = 0.551	18.1 ^p = 0.000

Notes: ¹p-values: Ex-smokers are compared with never smokers. ²p-values: Smokers are compared with ex-smokers.

Table III.  Positive predictive value (PPV) of reported symptoms for any airflow limitation¹ and severe airflow limitation¹ for 2154 women and 1800 men 60 years and older.

	Any airflow limitation		Severe airflow limitation
	Women	Men	Women	Men
Reported symptoms	PPV (%)	PPV (%)	PPV (%)	PPV (%)
Wheezing	25.5	32.7	9.7	10.5
Dyspnoea on unhurried walking	30.7	36.4	15.9	16.4
Dyspnoea on quick walking	18.7	27.2	5.6	8.2
Daily cough in periods	26.6	35.4	10.1	10.8
Daily cough with phlegm	31.7	40.0	14.5	11.9
Chr. cough with phlegm	37.0	40.4	17.3	14.2

Notes: See notes 2 and 3 to Table I, respectively.

Table IV.  Odds ratios (OR), with 95% confidence intervals (CI), of gender, age, smoking status, and symptoms, in the development of any airflow limitation and severe airflow limitation, in 3919 subjects aged 60 years or more.

	Any airflow limitation		Severe airflow limitation
	OR	95% CI	OR	95% CI
Male gender	1.2	1.0–1.4	1.1	0.8–1.6
Age over 70	1.0	1.0–1.0	1.1	1.0–1.1
Ex-smoker	2.4	1.9–3.1	2.4	1.4–4.0
Current smoker	5.8	4.5–7.5	3.3	1.9–5.6
Wheezing	1.5	1.2–1.8	2.4	1.7–3.5
Dyspnoea on unhurried walking	1.8	1.2–2.6	2.4	1.4–4.1
Dyspnoea on quick walking	1.4	1.1–1.6	2.4	1.6–3.6
Daily cough	1.1	0.8–1.5	1.3	0.8–2.2
Daily cough with phlegm	1.6	1.1–2.4	1.6	0.9–3.0
Chronic cough with phlegm	1.2	0.8–1.7	1.4	0.8–2.5

Notes: See notes 2 and 3 to Table I, respectively.

Table V.  The risk of having any airflow limitation¹ or severe airflow limitation¹ according to number of symptoms (wheezing, both forms of dyspnoea, and cough with phlegm), according to smoking status, in 3919 subjects aged 60 years or more (women and men are analysed together).

	Never smokers			Ex smokers			Current smokers
Number of symptoms	n	Moderate to severe airflow limitation (%)	Severe airflow limitation (%)	n	Moderate to severe airflow limitation (%)	Severe airflow limitation (%)	n	Moderate to severe airflow limitation (%)	Severe airflow limitation (%)
0	688	5.1	0.6	735	10.6	1.1	317	31.2	2.8
1	443	6.3	1.6	556	15.6	2.9	293	32.4	4.4
2	155	15.5	4.5	295	27.1	10.5	201	36.8	9.5
3	40	15.0	5.0	90	44.4	20.0	106	52.8	22.6

Note: See notes 2 and 3 to Table I, respectively.

Figure 1.  Diagnostic values of a three-symptom score for any airflow limitation and severe airflow limitation for women and men together. Note: AUC = area under curve.