Table 3. Age-Standardized All-Cause and Cause-Specific Mortality Ratios for the Unsheltered Cohort (2000-2009) Compared With the Massachusetts Population (2000-2009) and With a Sheltered Adult Homeless Cohort (2003-2008)^a.

Underlying Cause of Deathb	Overall Deaths, No. (%) (n = 134)	SMR (95% CI)c
		Unsheltered Homeless Adults vs MA Population	Unsheltered vs Sheltered Homeless Adults
All causes for entire cohort	134 (100)	9.8 (8.2-11.5)	2.7 (2.3-3.2)
Natural causes
Cancer	21 (15.7)	4.8 (3.1-7.3)	2.8 (1.8-4.2)
Heart diseases	18 (13.4)	6.4 (3.9-9.9)	2.4 (1.4-3.7)
Chronic substance use	16 (11.9)	88.9 (52.7-141.5)	4.2 (2.5-6.7)
Chronic liver disease	15 (11.2)	32.2 (18.7-51.9)	4.5 (2.6-7.3)
HIV/AIDS	10 (7.5)	63.8 (32.4-113.8)	3.4 (1.7-6.0)
Ill-defined conditions	5 (3.7)	26.8 (9.8-59.3)	NC
External causes
Nonpoisoning injuriesd	19 (14.2)	33.3 (20.7-51.1)	7.1 (4.4-11.0)
Drug overdose	8 (6.0)	14.1 (6.5-26.7)	0.9 (0.4-1.7)e
Substance use disorder causes	39 (29.1)	43.6 (31.4-58.9)	2.5 (1.8-3.3)
Alcohol use disorder	30 (22.4)	110.2 (75.7-155.3)	NC
Opioid use disorder	9 (6.7)	15.7 (7.6-28.8)	NC

Abbreviations: ICD-10, International Statistical Classification of Diseases and Related Health Problems, Tenth Revision; MA, Massachusetts; NC, not calculated; SMR, standardized mortality ratio.

^aAdult sheltered homeless cohort from the study by Baggett et al.¹⁰

^bThere were no unknown causes of death, and fewer than 5 deaths in each category were suppressed.

^cThe SMR was calculated when there were 5 or more deaths in each category.

^dNonpoisoning injuries (ICD-10 diagnosis codes): transportation accidents (codes V01-V99), other external causes of accidental injuries (codes W00-X59, except X40-X49), and events of undetermined intent (codes Y20-Y34, except Y10-Y19). Methodology in combining the ICD-10 categories were based on the Health of Boston 2014-2015 report.¹⁵

^eThe SMR was not significant.