Low cholesterol levels are associated with higher rates of many infectious diseases

This study was published in Epidemiology and Infection 1998 Oct;121(2):335-47

Study title and authors:

Cohort study of serum total cholesterol and in-hospital incidence of infectious diseases.
Iribarren C, Jacobs DR Jr, Sidney S, Claxton AJ, Feingold KR.
Kaiser Permanente Division of Research, Oakland, CA 94611, USA.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/9825784

The study assessed the association between cholesterol levels and the risk of infections (other than respiratory and HIV) requiring hospitalisation. The study included 55,300 men and 65,271 women who were followed for 15 years.

The infectious diseases analysed in this study were thus classified:

o   Intestinal Infections: Salmonella, rotavirus (virus infection that can cause gastroenteritis).

o   Viral hepatitis.

o   Acute appendicitis.

o   All digestive and liver infections: Diverticulosis, abscess of the anal and rectal region, abscess of the intestine, liver disease, gallbladder inflammation, cholangitis(bile duct infection).

o   Endocarditis (inflammation of the inner layer of the heart).

o   Kidney infections.

o   Urinary tract infections.

o   All genito - urinary infections: cystitis, prostatitis, orchitis and epididymitis(inflammation of the testicles).

o   Venereal diseases: Syphilis, gonorrhoea, chlamydia, trichomoniasis (sexually transmitted infection).

o   Muscle – skeletal infections: Arthropathy(disease of the joints), Infective myositis(skeletal muscle infection), osteomyelitis (infection of the bone or bone marrow),  periostitis (inflammation of the periosteum, a layer of connective tissue that surrounds bone).

o   Skin and subcutaneous tissue: Herpes, eczema, ringworm, thrush, carbuncle, boils, cellulitis (common skin infection caused by bacteria), lymphadenitis (swollen or enlarged lymph nodes), impetigo (bacterial skin infection), pilonidal cyst (cyst or abscess under the skin of the buttocks), pyoderma(skin infection that exudes pus).

o   Septicaemia, bacteraemia.

o   Gangrene.

o   Central and peripheral nervous system: Meningitis, encephalitis (inflammation of the brain), myelitis (inflammation of the spinal cord), abscess on the brain, abscess on the spinal cord.

o   Endotoxic shock (septic shock).

o   Gynaecological: Salpingitis (infection and inflammation in the fallopian tubes), oophoritis (inflammation of the ovaries), pelvic inflammatory disease (bacterial infection of the female upper genital tract, including the womb, fallopian tubes and ovaries), cervicitis (inflammation of the uterine cervix), vaginitis (inflammation of the vagina),  bartholin cyst or abscess, (infection of the bartholin's glands which lie next to the entrance to the vagina).

The study found for men:

(a) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 29% increased risk of been hospitalised with any infection compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(b) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 9% increased risk of been hospitalised with intestinal infections compared to men with higher cholesterol levels between 4.14-5.15 mmol/L (160-200 mmol/L).
(c) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 63% increased risk of been hospitalised with viral hepatitis compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(d) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 1% increased risk of been hospitalised with acute appendicitis compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(e) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 15% increased risk of been hospitalised with all digestive and liver infections compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(f) Men with lower cholesterol levels between 4.14-5.15 mmol/L (160-200 mmol/L) had a 22% increased risk of been hospitalised with endocarditis compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(g) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 10% increased risk of been hospitalised with kidney infections compared to men with higher cholesterol levels between 5.16-6.19 mmol/L (200-240 mg/dL).
(h) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 27% increased risk of been hospitalised with urinary tract infections compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(i) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 18% increased risk of been hospitalised with all genito-urinary infections compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(j) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 140% increased risk of been hospitalised with venereal diseases compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(k) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 28% increased risk of been hospitalised with muscle-skeletal infections compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(l) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 22% increased risk of been hospitalised with skin and subcutaneous tissue infections compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(m) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 17% increased risk of been hospitalised with Septicaemia and bacteraemia compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(n) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 20% increased risk of been hospitalised with gangrene compared to men with higher cholesterol levels between 5.16-6.19 mmol/L (200-240 mg/dL).
(o) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 67% increased risk of been hospitalised with central and peripheral nervous system infections compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(p) Men with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 128% increased risk of been hospitalised with endotoxic shock compared to men with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).

For women the study found:

(a) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 30% increased risk of been hospitalised with any infection compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(b) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 67% increased risk of been hospitalised with intestinal infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(c) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 51% increased risk of been hospitalised with viral hepatitis compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(d) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 22% increased risk of been hospitalised with acute appendicitis compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(e) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 19% increased risk of been hospitalised with all digestive and liver infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(f) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 137% increased risk of been hospitalised with endocarditis compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(g) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 9% increased risk of been hospitalised with kidney infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(h) Women with lower cholesterol levels between 4.14-5.15 mmol/L (160-200 mmol/L) had a 28% increased risk of been hospitalised with urinary tract infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(i) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 33% increased risk of been hospitalised with all genito-urinary infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(j) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 90% increased risk of been hospitalised with venereal diseases compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(k) Women with lower cholesterol levels between 5.16-6.19 mmol/L (200-239 mg/dL) had a 4% increased risk of been hospitalised with muscle and skeletal infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(l) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 15% increased risk of been hospitalised with skin and subcutaneous tissue infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(m) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 39% increased risk of been hospitalised with Septicaemia and bacteraemia compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(n) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 93% increased risk of been hospitalised with gangrene compared to women with higher cholesterol levels between 4.14-5.15 mmol/L (160-200 mmol/L).
(o) Women with lower cholesterol levels between 5.16-6.19 mmol/L (200-239 mg/dL) had a 9% increased risk of been hospitalised with central and peripheral nervous system infections compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(p) Women with lower cholesterol levels between 5.16-6.19 mmol/L (200-239 mg/dL) had a 44% increased risk of been hospitalised with endotoxic shock compared to women with higher cholesterol levels over 6.2 mmol/L (240 mg/dL).
(q) Women with lower cholesterol levels below 4.14 mmol/L (160 mg/dL) had a 2% increased risk of been hospitalised with gynaecological infections compared to women with higher cholesterol levels between 5.16-6.19 mmol/L (200-240 mg/dL).

The results of this study show that low cholesterol levels are associated with higher rates of many infectious diseases.