The affect is actually positive in terms of building buyer confidence. If a searcher sees that your site ranks well in the organic SERPs and it also appears in the Sponsored results, studies have indicated that you appear more trustworthy and conversions tend to be higher.
In terms of SEO it helps for Pay Per Click Ad but more on targeting the right keywords in exact or broad keywords. Page rank does not correlate with Pay Per Click as its more focus on the link building of the site.