From The American Heritage Dictionaries (cited here, suffer: Definition, Synonyms and Much More from Answers.com)
USAGE NOTE In general usage the preferred preposition after suffer is from, rather than with, in constructions such as He suffered from hypertension. Ninety-four percent of the Usage Panel found suffered with unacceptable in the preceding example. In medical usage suffer with is sometimes employed with reference to the pain or discomfort caused by a condition, while suffer from is used more broadly in reference to a condition, such as anemia, that is detrimental but not necessarily painful.
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