Physical Activity and All-cause Mortality: An Updated Meta-analysis with Different Intensity Categories

Abstract

In a meta-analysis we investigated the effect of physical activity with different intensity categories on all-cause mortality. Many studies have reported positive effects of regular physical activity on primary prevention. This recent meta-analysis analyzed all-cause mortality with special reference to intensity categories. A computerized systematic literature search was performed in EMBASE, PUBMED, and MEDLINE data bases (1990–2006) for prospective cohort studies on physical leisure activity. Thirty-eight studies were identified and evaluated. The presentation refers to studies with 3 or 4 different intensities of regular physical activity according to a standard questionnaire. There was a significant association of lower all-cause mortality for active individuals compared with sedentary persons. For studies with three activity categories (mildly, moderately, and highly active) and multivariate-adjusted models, highly active men had a 22% lower risk of all-cause mortality (RR=0.78; 95% CI: 0.72 to 0.84) compared to mildly active men. For women, the relative risk was 0.69 (95% CI: 0.53 to 0.90). We observed similar results in moderately active persons compared to mildly active individuals (RR=0.81 for men and RR=0.76 for women). This association of activity to all-cause mortality was similar and significant in older subjects. Regular physical activity over longer time is strongly associated with a reduction in all-cause mortality in active subjects compared to sedentary persons. There is a dose-response curve especially from sedentary subjects to those with mild and moderate exercise with only a minor additional reduction with further increase in activity level.

primary prevention - physical training - fitness - aging - gender

References

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Appendix A

Tables A1-A8

Table A1 Studies with two intensity groups of physical activity.

First author (year)	Country	Follow-up (yrs)	Sex	Adjustment	Age group	Number of participants	RR in the active group+(95% CI)
Kaplan (1996)	USA	28	all	multivariate	3	6 131	0.84 (0.77–0.92)
Knoops (2004)	Europe	10	all	multivariate	2	2 339	0.63 (0.55–0.72)
Hedblad (1997)	S	25	men	age	1	642	0.68 (0.49–0.94)
Hedblad (1997)	S	25	men	multivariate	1	642	0.70 (0.50–0.98)
Villeneuve (1998)	CDN	7	men	multivariate	1	6 246	0.82 (0.65–1.04)
Schnoor (2000)	DK	22	men	multivariate	3	4 658	0.39 (0.19–0.73)
Panagiotakos (2004)	GR	40	men	multivariate	1	529	0.83 (0.66–1.02)
Villeneuve (1998)	CDN	7	women	multivariate	1	8 196	0.88 (0.68–1.04)
Definition of age group: 1=”<65 years”, 2=”≥65 years”, 3=”all ages”

Table A2 Studies with three intensity groups of physical activity: Sex=all.

First author (year)	Country	Follow-up (yrs)	Adjustment	Age group	Number of participants	RR in the moderate active group+(95% CI)	RR in the most active group+(95% CI)
LaCroix (1996)	USA	5	age	2	1 645	0.69 (0.46–1.06)	0.73 (0.48–1.10)
Kujala (1998)	FIN	19	age	1	15 902	0.71 (0.62–0.81)	0.57 (0.45–0.74)
Hillsdon (2003)	GB	12	age	1	10 522	0.57 (0.42–0.79)	0.72 (0.54–0.95)
LaCroix (1996)	USA	5	multivariate	2	1 645	0.83 (0.53–1.29)	0.91 (0.58–1.42)
Kujala (1998)	FIN	19	multivariate	1	15 902	0.80 (0.69–0.91)	0.76 (0.59–0.98)
Hillsdon (2003)	GB	12	multivariate	1	10 522	0.63 (0.45–0.89)	0.81 (0.60–1.09)

Table A3 Studies with three intensity groups of physical activity: Sex=men.

First author (year)	Country	Follow-up (yrs)	Adjustment	Age group	Number of participants	RR in the moderate active group+(95% CI)	RR in the most active group+(95% CI)
Leon (1991)	USA	10.5	age	1	12 138	0.85 (0.73–0.99)	0.87 (0.74–1.01)
Paffenbarger (1993)	USA	9	age	3	10 269	0.70 (0.54–0.88)	0.68 (0.54–0.95)
LaCroix (1996)	USA	5	age	2	615	0.78 (0.43–1.45)	0.89 (0.49–1.62)
Morgan (1997)	GB	10	age	2	635	0.62 (0.38–1.00)	0.36 (0.26–0.51)
Rosengren (1997)	S	20	age	1	7 142	0.74 (0.68–0.82)	0.73 (0.68–0.79)
Bijnen (1998)	NL	10	age	2	802	0.67 (0.52–0.85)	0.64 (0.50–0.83)
Hakim (1998)	USA	12	age	2	707	0.64 (0.38–1.12)	0.53 (0.34–0.77)
Andersen (2000)	DK	14.5	age	3	17 265	0.71 (0.66–0.76)	0.65 (0.59–0.70)
Yu (2003)	GB	11	age	1	1 975	0.88 (0.66–1.18)	0.58 (0.41–0.82)
Barengo (2004)	FIN	20	age	1	15 853	0.85 (0.79–0.92)	0.60 (0.53–0.68)
Leon (1991)	USA	10.5	multivariate	1	12 138	0.89 (0.77–1.04)	0.92 (0.79–1.07)
Lindsted (1991)	USA	26	multivariate	1	9 484	0.68 (0.59–0.78)	0.76 (0.63–0.92)
Mensink (1996)	D	8	multivariate	1	954	0.61 (0.35–1.05)	0.79 (0.48–1.31)
Morgan (1997)	GB	10	multivariate	2	635	0.85 (0.52–1.39)	0.63 (0.44–0.89)
Rosengren (1997)	S	20	multivariate	1	7 142	0.84 (0.77–0.93)	0.83 (0.77–0.90)
Bijnen (1998)	NL	10	multivariate	2	802	0.80 (0.63–1.02)	0.77 (0.59–1.00)
Hakim (1998)	USA	12	multivariate	2	707	0.62 (0.36–1.08)	0.56 (0.37–0.83)
Sherman (1999)	USA	16	multivariate	3	962	0.85 (0.77–0.94)	0.80 (0.70–0.89)
Andersen (2000)	DK	14.5	multivariate	3	17 265	0.72 (0.66–0.78)	0.71 (0.65–0.78)
Yu (2003)	GB	11	multivariate	1	1 975	0.87 (0.65–1.17)	0.61 (0.43–0.86)
Barengo (2004)	FIN	20	multivariate	1	15 853	0.91 (0.85–0.98)	0.80 (0.71–0.90)

Table A4 Studies with three intensity groups of physical activity: Sex=women.

First author (year)	Country	Follow-up (yrs)	Adjustment	Age group	Number of participants	RR in the moderate active group+(95% CI)	RR in the most active group+(95% CI)
LaCroix (1996)	USA	5	age	2	1 030	0.50 (0.28–0.90)	0.45 (0.25–0.83)
Kushi (1997)	USA	7	age	1	40 417	0.66 (0.60–0.73)	0.58 (0.52–0.65)
Morgan (1997)	GB	10	age	2	635	0.61 (0.40–0.92)	0.36 (0.27–0.48)
Andersen (2000)	DK	14.5	age	3	13 375	0.64 (0.59–0.69)	0.55 (0.49–0.62)
Barengo (2004)	FIN	20	age	1	16 824	0.85 (0.77–0.94)	0.87 (0.74–1.02)
Lissner (1996)	S	20	multivariate	1	1 405	0.56 (0.39–0.82)	0.45 (0.24–0.86)
Mensink (1996)	D	8	multivariate	1	1 142	0.94 (0.51–1.75)	0.81 (0.44–1.49)
Kushi (1997)	USA	7	multivariate	1	40 417	0.77 (0.69–0.86)	0.68 (0.60–0.77)
Morgan (1997)	GB	10	multivariate	2	635	0.73 (0.48–1.12)	0.48 (0.36–0.65)
Sherman (1999)	USA	16	multivariate	3	1 410	0.84 (0.76–0.93)	0.83 (0.75–0.90)
Andersen (2000)	DK	14.5	multivariate	3	13 375	0.65 (0.60–0.71)	0.59 (0.52–0.67)
Barengo (2004)	FIN	20	multivariate	1	16 824	0.90 (0.82–0.99)	0.98 (0.83–1.15)

Table A5 Studies with four intensity groups of physical activity: Sex=all.

First author (year)	Country	Follow-up (yrs)	Adjustment	Age group	Number of participants	RR in the light active group+(95% CI)	RR in the moderate active group+(95% CI)	RR in the most active group+(95% CI)
Andersen (2000)	DK	14.5	age	3	30 640	0.68 (0.64–0.71)	0.61 (0.57–0.66)	0.53 (0.41–0.68)
Hillsdon (2003)	GB	12	age	1	7 704	0.68 (0.45–1.05)	0.40 (0.27–0.58)	0.40 (0.28–0.57)
Hillsdon (2003)	GB	12	multivariate	1	7 704	1.14 (0.74–1.78)	0.53 (0.35–0.82)	0.52 (0.35–0.78)

Table A6 Studies with four intensity groups of physical activity: Sex=men.

First author (year)	Country	Follow-up (yrs)	Adjustment	Age group	Number of participants	RR in the light active group+(95% CI)	RR in the moderate active group+(95% CI)	RR in the most active group+(95% CI)
Morris (1990)	GB	9.5	age	1	9 376	0.88 (0.66–1.17)	0.78 (0.54–1.12)	0.34 (0.18–0.66)
Eaton (1995)	ISR	21	age	3	8 463	0.84 (0.74–0.94)	0.81 (0.73–0.90)	0.84 (0.72–0.98)
Leon (1997)	USA	16	age	1	12 138	0.78 (0.67–0.91)	0.77 (0.66–0.90)	0.74 (0.63–0.86)
Wannamethee (1998)	GB	4	age	3	5 934	0.57 (0.40–0.78)	0.39 (0.25–0.62)	0.48 (0.34–0.68)
Morris (1990)	GB	9.5	multivariate	1	4 824	0.90 (0.57–1.44)	0.59 (0.34–1.05)	0.53 (0.21–1.32)
Sandvik (1993)	N	16	multivariate	1	1 960	0.92 (0.66–1.28)	1.00 (0.71–1.41)	0.54 (0.32–0.89)
Haapanen (1996)	FIN	11	multivariate	1	1 072	0.40 (0.21–0.75)	0.64 (0.34–1.20)	0.37 (0.19–0.68)
Folsom (1997)	USA	7	multivariate	1	6 188	0.83 (0.60–1.14)	0.97 (0.65–1.45)	0.68 (0.47–0.99)
Leon (1997)	USA	16	multivariate	1	12 138	0.85 (0.73–0.99)	0.87 (0.75–1.02)	0.83 (0.71–0.97
Erikssen (1998)	N	13	multivariate	1	1 428	0.72 (0.52–0.99)	0.48 (0.33–0.71)	0.45 (0.29–0.69)
Villeneuve (1998)	CDN	7	multivariate	1	6 246	0.81 (0.59–1.11)	0.79 (0.54–1.13)	0.86 (0.61–1.22)
Wannamethee (1998)	GB	4	multivariate	3	5 934	0.61 (0.43–0.86)	0.50 (0.31–0.79)	0.65 (0.45–0.94)
Breckenkamp (2004)	D	14	multivariate	1	2 320	0.62 (0.35–1.08)	0.76 (0.45–1.29)	0.44 (0.30–0.65)

Table A7 Studies with four intensity groups of physical activity: Sex=women.

First author (year)	Country	Follow-up (yrs)	Adjustment	Age group	Number of participants	RR in the light active group+(95% CI)	RR in the moderate active group+(95% CI)	RR in the most active group+(95% CI)
Weller (1998)	CDN	7	age	3	6 620	0.91 (0.66–1.25)	0.94 (0.72–1.23)	0.89 (0.67–1.17)
Folsom (1997)	USA	7	multivariate	1	7 852	0.79 (0.53–1.18)	1.05 (0.66–1.66)	0.58 (0.36–0.92)
Villeneuve (1998)	CDN	7	multivariate	1	8 196	0.94 (0.69–1.30)	0.92 (0.64–1.34)	0.71 (0.45–1.11)
Breckenkamp (2004)	D	14	multivariate	1	2 320	0.34 (0.14–0.81)	0.39 (0.17–0.91)	0.23 (0.12–0.42)

Table A8 Studies with five intensity groups of physical activity.

First author (year)	Country	Follow-up (year)	Sex	Adjustment	Age group
Fried (1998)	USA	5	all	age	2
Fried (1998)	USA	5	all	multivariate	2
Sundquist (2004)	S	12	all	multivariate	2
Sundquist (2004)	S	12	men	age	2
Lee (1995)	USA	26	men	multivariate	1
Sundquist (2004)	S	12	women	age	2
Rockhill (2001)	USA	20	women	age	1
Rockhill (2001)	USA	20	women	multivariate	1
First author (year)	Number of participants	RR in the light active group+(95% CI)	RR in the moderate active group+(95% CI)	RR in the active group+(95% CI)	RR in the most active group+(95% CI)
Fried (1998)	5 201	0.62	0.55	0.43	0.29
		(0.49–0.80)	(0.43–0.70)	(0.34–0.55)	(0.23–0.38)
Fried (1998)	5 201	0.78	0.81	0.72	0.56
		(0.60–1.00)	(0.63–1.05)	(0.55–0.93)	(0.43–0.74)
Sundquist (2004)	3 206	0.72	0.60	0.50	0.60
		0.64–0.81)	(0.50–0.71)	(0.42–0.59)	(0.46–0.79)
Sundquist (2004)	1 414	0.74	0.57	0.51	0.60
		(0.62–0.87)	(0.44–0.73)	(0.41–0.64)	(0.44–0.82)
Lee (1995)	17 321	0.88	0.92	0.87	0.87
		(0.82–0.96)	(0.82–1.02)	(0.77–0.99)	(0.78–0.97)
Sundquist (2004)	1 792	0.70	0.59	0.47	0.54
		(0.59–0.82)	(0.46–0.77)	(0.35–0.62)	(0.31–0.94)
Rockhill (2001)	4 746	0.76	0.66	0.64	0.62
		(0.70–0.82)	(0.61–0.71)	(0.58–0.70)	(0.54–0.72)
Rockhill (2001)	4 746	0.82	0.75	0.74	0.71
		(0.76–0.89)	(0.69–0.81)	(0.68–0.81)	(0.61–0.82)
(Above: Authors,Country,Follow-up,Sex,Adjustment, Age; Below:No of participants,RR according to the groups compared to sedentary group)

Correspondence