Objective. To estimate net savings and cost effectiveness
obtained through the use of 50-100 mg/oral
of Sildenafil for Erectile Dysfunction (ED) as a coadjuvant
in pharmacological treatment adherence
in patients with Hypertension and Type 2 Diabetes
versus ED treatment options: non-treatment, 10-
20 mg/oral Vardenafil and 20 mg/oral Tadalafil, in
the Instituto Mexicano de Seguro Social (Mexican
Social Security Institute) (IMSS).
Methods. With a decision tree model, a random,
retrospective sample of 1,000 hypertensive
patients and 1,000 diabetic patients, all presenting
with ED, was created from a total of 13,731
IMSS patients hospitalized for hypertension and
65,523 for diabetes in 2005 (SUI-13 IMSS national
database) to determine resource use. The study effectiveness
measures were ED treatment success,
reduced treatment abandonment rate for hypertension
and for diabetes, and avoided hospital stay
(for diabetes, hypertension and respective chronic
complications). These measures were estimated
through analysis of the scientific literature on the
subject and through prospective research with an
instrument developed ex profeso and applied by
telephone to a representative Mexico City population
of 326 hypertensive patients and 146 diabetic
patients. The study horizon was 1 year with projections
at 5 and 10 years after treatment initiation,
from the perspective of the public health service
provider (IMSS) as well as from a social perspective.
ED pharmacological management was carried out
with 50-100 mg/oral of Sildenafil and compared
with the options of non-treatment, treatment with
20 mg/oral of Tadalafil and 10–20 mg/oral of Vardenafil.
Results were expressed in US dollars from
the year 2006. Sensitivity analysis for each base pathology
was carried out individually, starting from
cost modifications per patient, effectiveness rates
and frequency of chronic complications.
Results. A 50mg dose of Sildenafil was the treatment
alternative with the lowest annual cost: in DM
2,609.11 – 2,932.23 USD (CI 95%; P = 0.0001), and in
HTN 2,812.13 – 3,032.69 USD (CI 95%; P = 0.0001)
and represented a cost-saving ED therapy versus
non-treatment. In DM, a year of ED treatment with
50mg of Sildenafil versus ED non-treatment option
produced a savings of 753.13 – 829.94 USD (CI
95%; P = 0.0001); 3,213.02 – 3,624.21 USD (CI 95%;
P = 0.0000) at 5 years of treatment; and 12,070.08
– 13,301.39 USD (CI 95%; P = 0.0001) at 10 years
of treatment. In HTN, a year of ED treatment with
50mg of Sildenafil versus ED non-treatment option
produced a savings of 1,540.54 – 1,667.10 USD (CI
95%; P = 0001); 5,475.72 – 7,190.28 USD (CI 95%;
P = 0.0000) at 5 years; and 24,325.00 – 26,741.22 USD
(CI 95%; P = 0.0001) at 10 years. In relation to effectiveness,
14 DM and HTN patients with ED avoided
hospitalization (CI 95%) when treated with 50mg
of Sildenafil, while 18 DM and HTN patients with
ED avoided hospitalization (CI 95%) when treated
with 100mg of Sildenafil.